Cristiano Ronaldo or Lionel Messi, who is more consistent in scoring goals? The evidence from CFM exploratory analysis

The rivalry between two football superstars Cristiano Ronaldo and Lionel Messi has always been a subject of extensive discussion. This study aimed to compare the level of consistency between the two players in scoring goals through 6 ways: right-foot…

Authors: Samsul Anwar, Siti Munawarah, Radhiah Radhiah

Cristiano Ronaldo or Lionel Messi, who is more consistent in scoring goals? The evidence from CFM exploratory analysis
POST-PRINT acce pted for publication in M ovem ent & Sport Sciences - Science & M otr icité Cristiano Ronaldo or Lionel Messi, who is m ore consistent in sc oring goals? The evidence from CFM exploratory analysis Sams ul Anwar 1 ,* , S iti Munawa rah 2 , Radhiah Radhiah 3 1 ,2 Uni versitas Syiah Kuala, Department of Statist ic s, Banda A ceh , Indonesia 3 Uni versitas Syiah Kuala, Department of Mathematics, Banda Aceh, Indonesia Received 27 February 2024, Accepted 7 Novem ber 2025, Publish ed 29 Marc h 2026 Abs tr ac t - - The rivalry be twee n two f oot ball super stars Cris t i ano Ronal do and Li onel Mess i ha s alwa ys been a subject of extensive disc ussion. This s t ud y a imed to com pare the l evel of consis t e ncy b etween the two playe rs in sco r in g go als t hrough 6 way s: r i g ht -footed ki cks, l e f t - footed kicks , penal t y k icks, direct f r ee k i ck s, l o ng-range kicks, and headers. The dat a analy zed wa s the durat i o n of t ime ( minutes) each playe r too k to s core a goal in ever y match they played. The data was obtained f ro m a f o otball we bsite call ed Transfermarkt.com. Co m pet in g Failure Modes (CF M) was used to measure the reli a bili t y of t he two pl a yers in sco rin g goa ls based on t hose vario us ways . The resu l t s of CFM e xpl o rat ory ana lysis sh o wed that Ronal do an d Messi h ad the sa me l e vel of consis t e ncy in scor ing go als f or m o re t han 17 years of t hei r pro f e ssional f o ot ball career. Bot h hav e b ee n am o n g m o st ta l e nted players in the m o der n foot ball era w i t h individual and t eam achievem ents t hat are f ar a bove other footballers around the wo rl d . Keywords : compe t ing fail ure m o des, foot ball , go al sco r in g r eliabili t y , tr ansf ermarkt Résumé - Cristiano Ronaldo ou Lionel Messi, qui est le plus régul ier p our marquer des but s? Une preuve t irée des r ésu ltats de l’anal yse exploratoire CFM. La riv a li t é e ntre le s deux superstar s du f o o tball Cris tiano Ronal do et L i o nel Messi a t oujours fai t l' o bjet de nombreuses discussi o n s. Cett e étude visai t à co m parer le niveau de co héren ce e ntre les deux joueurs da ns la not ation des buts de 6 m a nières: coups de pi ed dro i t , coups de pi ed gauche, t i rs au but, co ups fran c s di r ects, coups de pi ed lointains et coups de t ête. Les do nn ées analysées ét ai e nt la dur ée (mi nut es) que chaque j o ueur m et t ai t pour marquer un but dans chaque m at ch qu 'il a d i sput é. Les donn ées o nt été o btenue s à part i r d'un site web de f ootball appel é T ransfermarkt.co m . Des Com pet i ng F ailure M o des ( CFM ) ont été utilisés pour m esurer la fi a bilité des deux j o ueurs à marquer des buts en f o nct i o n de ces diffé rentes maniè res. Les résul t ats de l' a nalyse expl o rato ire du CFM ont m ont ré que R o nal do et Mes s i avaient m ê me nivea u de régul ar i t é po ur ce qui est de marquer de buts pendant plus de 17 ans de leur carriè re de footballeur pro f essionne l . T ous deux compten t parm i l e s j o ueurs l es pl u s tal ent ueux de l'ère du f o otball moderne, av ec des réalisat ions individuelles et co ll ect iv es bien supérieures à celles des aut res footballe urs du monde. Mots clés: m o des de déf aillance co ncurrents, football , fiabili té des buts marqués , t ransf ermarkt *Corresponding author: sams ul.a nwa r @us k. ac.id This articl e has been peer-reviewe d and accepted for public at i o n in t he j o urnal “M ovement & Sport Sci e nces – Sci e nce & Motrici t é” on November 7, 2025. The j o urnal is cu rrently transi t i o ning to Episci ences, a diamond open access publishing platform , and t his arti cle wil l be made freely available on t he new website of t he journal at t he en d of t hi s t ransi t i o n. 2 1 Introductio n Football is the world's m o st popula r sport si nce it is pl a yed in a lm ost every country aro und the wor l d ( Busey & W ar in g, 2012 ). Th e worl d football f ed eration, F éd érat i o n Int ernati o nale de Football Associati on ( FIFA), est im at es t hat there are currently around 250 m il li o n football players and m o re t han 1.3 billi o n people in t erest ed in f oot ball ( Giulianott i et al ., 2021 ) . Every o ne in foot ball starting from gen era l managers and coachin g sta ff to fans and media are in terest ed in evaluat in g playe r ’s perfor m a nce ( Pelechrini s & Wins t o n, 2021 ). His t o ric a lly, f o otball has had many t alen t ed p lay ers who serve as ins pirational m ode ls f o r young f o ot ball ers and are st il l discussed a nd f o ll o wed to day . A f o ot ball legend is a p l a yer who man aged to carve his name in the f o ot bal l his tory books, not only b ased on his personal success records, but also for a t eam he played on. In t he m o dern era of foo tball in t he 21st century, there are t wo pl a yers w ho are a lways associ ated wi t h each other, nam e ly C r ist i a no Ronaldo and Li o nel Messi. Apa rt f ro m Ronal do and Messi, there are in deed se veral o ther fam o u s m o der n f o ot ball p layers such as Zlatan Ibrahim o vić, Ne ymar, Luis Suár ez, Moham ed Salah, Ro bert Lewa ndowski , K ar im Benzem a a nd ot hers. But al l t hese p layers hav e been rarely in the media spot li ght li ke Ro naldo and Messi since t hese two playe r s p layed on the well regarded Spanish La Li ga c lubs, namely Re al Madrid C.F. and FC Barce l o n a in 2009. Ac cord ing to Castañer et al . (2017) , both are c onsi d ered the best f o ot ball players ev er. Ronal do and Messi w ere l is ted as the m o st f oot ball er s to win the FIFA Best P layer award or known as t he FIFA Ball o n d' Or . F rom 2008 to 2023 , Mes s i won 8 times and Ronaldo 5 time s. In add i t i o n, t hes e two f o ot ball superstars have made numerous achiev ements. Base d on tro phi es at c l u b level, Messi has wo n 38 trophies w i th FC Barcel o na, Paris Sain t -Ger main F.C. a nd Inter M iami CF w hile Ronal do has won 31 tro phi e s t hroughout his career at sev era l clubs he has p layed f o r, in c luding S port in g CP, Manches t er Uni t ed F.C., Real Madrid C.F., Juv e ntus F .C. and Al Nassr FC. Furthermore, f o r t rophies with t he nat i onal t eam , Ronaldo succeede d in bringing Portugal to wi n two t rophies, n a m ely t he UEFA Euro 2016 Cup an d t he 2019 UEFA Na tions L eague. On the other hand, Mes s i m a naged to bring Argentina to win the Copa América (2021 and 2024) a nd t he 2022 W o rl d Cup. There are many o t her in d ividual a nd tea m ac hievemen ts of t he two playe r s t hat are not m e nt i o ned here. We can easily find it in their bi o grap hies which are published in vari o us exist ing li t erat ure. The debate o ver who is greater between Ronaldo and Messi w ill never stop until both h a ng up t hei r boot s. A cco rding to S he rgo l d (2016) , t he debate ab o ut t hese two f o ot ball superstars will neve r end. These t wo fi gures have be e n very attractive to t he football wo rld co mmuni t y . T ia go et al . (2016) claime d t hat f o r most athl et es includin g f o ot ball p layers, soc i a l media is a powerful t oo l to t ake advan t age of their t im e in the spotligh t. Fa ns of bot h wil l never t ire of cl a iming t hei r respective i do ls as the best one. A study by Kassing (2020) sh o wed t hat fans used in t er net sport s m e mes to beli t t le of their r iv a l oppo nen t s and idolize thei r o wn play er s. Based on the data c o ll ected in a sport, rese ar che r s are able to perform qua nti tat ive analysis on t he perf or mance of p layers and t eams ( Rahimi an & T oka, 2022 ). C o nsisten cy in showing the b est perf o r m a nce in every ma tch is an important i ndicato r in assessing t he career path of a professi o n a l foot ball player. In order to p rove who is m o re domi na nt b etween these two most fam o us p l a yers, sev eral sc ientifi c studies have b een conducted. A research by Castañer et al . (2016) usin g a p o lar c oo rdina te analy s is appro ach s hows t hat Messi is a p layer who is m o re dominant in using his lef t foot. Messi has excellent laterali t y skills (left-right brain balance ) as a f o otball player. Furt herm o re, Shergold ( 2016) , who c o nducted resea rch us ing desc r i pt i ve compa rat ive analysis w hen bot h p l a yed in t he Spanish La Li ga since t he 2009-10 season st ated t hat Messi mana ged to score 270 goals in 252 matches, p lay ed for 21,218 mi nut es and s hot 953 times . Ronaldo m a naged to sc or e 270 goals in 247 m at ches, playe d f o r 21,206 minutes and s hot 1,318 tim e s. The study sh o wed t hat Messi ha d a shot conv ersion rat e of 28. 77%, whil e Ronal do had 20. 03%. Apart f ro m having a high level of accuracy , bot h als o have unique ness in m o t o r s k ills t hat are diffe r ent from other football players. Magee ( 2025) sh o wed that h a vin g more attack in g pl a yers on the p i t ch will re sult a higher rat e of scoring goals, signifying the im po rtance of the f o rwards in helping the team to secure t he game . Various studies fro m several co mpe t i t io ns denoted around 40 to 50% of goals were sco red by at tacking players, indicating a consis tency in scor in g goal s is im po rtant and represen t t he abili t y of a f oot ball er , especially forwards, in adapting t he ch a nge t hat occurs fro m a season to sea son ( Acar et al ., 2009 ; M. Mi t rot asi os & A r matas, 2014 ; Μ. Mi t rot asi os et al., 2006 ). Whe re t he opponents they mi g ht have fa ced were likely als o changed in t er m s of t hei r p laye r co mpositi o n, st rategy implemented, l e vel of p lay , a nd so o n. Accord in g ly, it is important to m e asure t he level of consistency in scoring goals over a long per i o d of t ime as an in d icator to co m pare the professi o nal c areer pat hs of Ronaldo and Messi as f o rwards. Unf o rt unately , the pr evi o us st udi e s hav e not b een able to an swer who had m o re co nsi st ent performanc e betwe en Cristiano Ronal do and L i o n e l Me ssi during their entire careers as professi o nal f o o t ball players. The co mpa r is on carr ied out in t he fi r st study f o cused m o re on com par ing the physic al a bili t ie s between t he t wo players , while t he co mparison in t he seco nd study w as m o re directed at t he performanc e between the two playe r s t hrough a nalysis using aggregate data espe c i ally w hen both were pl a ying in La Liga, so that the concl usio ns obtain ed are not ver y accurat e and only app ly to that t im e per i o d. To sci ent ifically pro ve who had m or e consi stent perf o r m ance be t wee n Ronaldo an d Mess i , this stud y employed an alternative appro ach based on tim e intervals to score a goal . To t he bes t of o ur kn o wl edge, t hi s is t he f irst study app lying t his approach in measuring r eli a bili t y of a foot ball player in scoring goals. Apart f ro m the number and durat i o n of t ime needed to score a go al , thi s st udy also consi dered different way s of scoring goals. In f o otball , there are several wa ys to score a go al , through penal t y kick, header, direct free k i ck, long-range k i ck, r i g ht- f o o ted kick an d left-footed ki ck. Each of these way s of scoring goals has a different level of d iffi c ult y . 3 Theref o re, t he objective of t he curr ent study was to compa re the go a l sc or ing re li a bili t y between Cr istiano Ro nal do and L i o n e l Messi to fin d o ut who h ad m o re c o nsis tent perf o r m ance be t wee n t he se t wo recognizabl e p l ayers dur ing their a lm ost ent i re ca reer as professi o nal foot ball p laye rs. This expl o rator y study has added some o bject iv e assessment indic ato rs f o r t hose who may require co m paring perfor m a nce of pro f e ssi o nal foo tball p layers, especi a lly between Ro naldo and Messi. 2 Met hods 2.1 Data, m ethods and vari ab l es Ac cord ing to Collett (2015) , surviv al a nalysis is st atis t i ca l analy s is of dur ation t ime data f r om t he beginning of the stud y until cert ain events occur. In this st ud y , t he event was de fined as go al s s cored by Cr ist i a no R onaldo and L i o nel Messi in ever y match they p layed. T he data examine d in t his st udy was the duration of t im e ( in mi nut es) each player took to sco re a goal cal culated s ince Ro naldo and Messi began to be dep l o y ed to play on the pitch . In general , survi va l data can be d ivi ded in t o 2, nam e ly cens ored data (in co mplete) and un ce ns or ed data (complete data). In t hi s study , when t he player successfully scored a goal durin g t he ga me, the time dur ation dat a was categoriz ed as u ncensored data. Conv ersely, if the player d i d not score any goa l , t he data was ca t egoriz ed as ce nsored data. Comm o nly, an even t that occurs in the obj ect of r esearch in sur vival a na ly s is is o nly c aused by o ne m o de. Howeve r, in practice , t he sam e event m ay o ccur due to sev e ra l possibl e m o des. Compe t i ng Failure Modes (CFM) an a lysi s is one of the analy t ical methods used to an a lyze t his su ch e vent ( Reli aSo ft, 2015 ). Jus t li k e ot her m et hods in survival analysis, CFM could also be appli e d to ot her various fiel ds. Th e curr ent s t udy tr ied to apply t his analys is in t he field of spo rt s, especially f o ot ball . In a f o ot ball ga me, a goal ca n be sco red in several wa ys ( m o des) such as through a r i g ht-foot ed kick, l e f t - foot ed kick, pe nal t y kick, free kick, l o ng-range k ick, and head header. CFM a nalysis was used to m easure the reli a bili t y of Ro naldo an d Messi in scorin g goals by considering those d ifferent way s of go als scored. Sim p ly put, CF M a nalysi s in this stud y measured the combine d reliabili t y of all t hese way s of s co ring goa ls. In other words, t he probabili t y of a p layer still n ot s coring any goa l a fter he p l a yed f o r a s pecifi c t im e period. Accordin gly, a pl ayer with l o wer re li a bility value was cons i d ered bett er in sco rin g goals than thei r co unterpart. To estim at e t he reli a bili t y value of each mode of t he ev e nt (a goal scored in t his stud y ), t he non-parametri c m ethod Ka plan-Me ier was used. We considered e mpl o ying a non- parame tr ic m et hod b ecause it di d n o t requi re ce r tain pro babili t y dis t r ibution a ssu mptions so t hat t he com par ison of t he dur ation of tim e taken to score a g o al between the t wo players was done without a need to di st inguish the probabili t y d istribut i o n of t he data. Through the CFM expl o rat ory analysis , it becam e k nown who was m o re co nsis t ent in s coring go als between Ronaldo and Messi . The da ta on t he dura t i on of t im e t aken by t he two playe rs to score g o al s used in this stud y was t he secondary dat a ex tr acted f r o m a German- ba sed foot ball we bsi t e called T ransfermarkt (https://www . transf ermark t. com/ ). The website has provi ded all inf o r m at i o n about f oot ball matches aro und t he wor ld including scores, resul t s, st atistics , t ransf er news , and fixtures and recorded all g ame s t at i st ics both f o r team s and players f o r eve ry seas on. Th ere w ere m o re than 60.000 ga mes f ro m many s easons in all major football co m pet i tions. The websi t e (at t he tim e of conductin g this stud y ) was available in f o urt een l anguages and the play er dat ab ase containe d deta il s of more than 800,000 professi o nal f o o t ball ers. Transfermarkt o b t a in ed dat a about these p layers f ro m m o re t han 1 milli o n of t heir r egis t ered users around the world who kept track of how many minutes each play er spends on t he pitch, m edical history, contra ct durati o n, and many more. Wi t h more than one billio n pa ge views per m o n t h, Transf er markt has beco m e o ne of t he wo rl d’s larges t f o o tball webs i t es. T he websi t e has b eco me the unoffi cial p laye r appraiser of t he football wor l d. Many t o p cl u bs an d i nter nat i o nal media ( e.g. E SPN, L' Équ i pe, The Guardian, and La Gazzett a dell o Spo rt) ci t e Transfe r markt as a source ( Keppel & C laessens, 2020 ). The data peri o d used in this study spans f r o m the 2002 - 03 seas on to t he 2020-21 s eason. Thi s per i o d was chosen because Ronal do began hi s prof essional career as a f o ot ball pl a ye r in t he 2002-03 seas o n, whil e Messi m ade his debut as a prof essiona l f o o tball player two seasons l ater. In analyzing t hes e two recognizabl e foot ball er s’ careers , Ro dri guez a nd Vill a blanca (2024) suggested an a ly z i ng the da ta since the beginning of t heir professi o nal career just like we d i d in t his study. In add i t ion, to reduce pot enti a l biases due to thi s different starting time career, we em p l o y ed a survival a nalysis approach t hat focused m o re on the durati o n of t i me an event o ccurs rather t han the number of samples analyze d. The variables analyzed in this stud y consisted of t he duration of t ime t aken to sc or e a goal ( T ), st atus of cens o ring data ( d ) and t he ways of go als scored ( X ) as shown in Ta ble 1. 2.2 Research procedures Data analy sis in this st udy was carried out separately between Cr istiano Ro nal do an d Li o nel Messi using R software versi o n 4.0. 3 with the survival package. T his study was conducted usi ng a nine-step pr o cedure. The first one was colle ct in g research d ata, nam e ly game stat ist i cs of Ronal do and Messi in all co mpe titions start i ng from the 2002 -03 seas o n to the 2020- 21 season. T he data co nsi sted of t he time durat ion nee d ed to score a g o al and ot he r v ar iables related to t hi s stud y . The second st ep was se paratin g the dat a f o r both p lay ers ba sed on t he way t he goals were scored ( pen alty k i ck, head header, direct f ree ki ck, long-range ki ck, right-footed ki ck an d lef t - f o o ted kic k). The thi rd one wa s conduct in g desc r ipt ive stat is tics analy s is to obtain an o vervi ew of t he data character i st ics of the time duration it too k f o r both pl ayer s to sc o re a g oa l . 4 Table 1. Study Var iables Var iab les Description Scale Category  Duration of time taken to score a goal ( in mi nutes) Rati o -  Status of censoring data Nominal 0 : Censored 1 : Uncensored  Way s of go als sc ored Nominal 1 : P enal t y Ki c k 2 : Head Header 3 : Direct Free Kick 4 : Long Dis tance Kick 5 : Right-Footed Kick 6 : Left-Foot ed Ki ck To quantify the per form a nce, t he playe r wh o had more goals per mi nut e of ga m e p lay ed was awarded 1 point, and t he total po ints earn ed by each pl a yer were com pared f o r t he fi rst half (minutes 1 - 45 ), s eco nd half ( minutes 46 - 90 minut es) and extra time ( mi nut es 91 - 120). The fourth o ne was e m ploying n o n-parametric Kaplan- Meier m ethod to estim at e t he r eliabili t y val ue of each way of scorin g goa ls f o r bot h playe r s. The Kaplan-Meier reli a bilit y value (   󰇛  󰇜 󰇜 was calculated us in g Equat i o n (1).   󰇛  󰇜             (1) whe re   is t he numbe r of events (i .e. go al s) t hat ha ppened at time   (time whe n at l east one eve nt happened) and   is number of obs er vat i o n t hat h a ve not y et had an event up to t im e   ( Re li aSo f t , 2015 ). The fi f t h step was perf o r mi ng L og Rank tests to e valuate the dif fere nce in Kaplan-Me ier r eli a bili t y cur ves be twee n Ronal do and Me ssi in each way of scorin g goa l s. The six t h one was est ima t in g the overall reliabili t y value (    󰇛󰇜 ) and its 95% c o nfiden ce intervals using C FM approach which was the pro duc t of reli a bili t y of e ac h ways of scor in g goals. The o verall reliabili t y value is defined as Equat i o n (2) .    󰇛  󰇜      󰇛 󰇜           ( 2) Note t hat if a modality of scorin g goa l was limi t ed, t hen CFM o nly consi dered the wa y of sco ring go als w ith a suf ficient number of go a l s. The e st im at e 95% confidence intervals of each ways of scor in g go als is defined as Equat i o n (3).    󰇛  󰇜   󰇛  󰇜   󰇛  󰇜        󰇛  󰇛  󰇜 󰇜   󰇛  󰇜 󰇡  󰇛  󰇜 󰇢    󰇛  󰇜   󰇛  󰇜   󰇛  󰇜        󰇛  󰇛  󰇜 󰇜   󰇛  󰇜 󰇡  󰇛  󰇜 󰇢  (3) whe re   󰇛  󰇛  󰇜 󰇜 is t he e st im ate variance of the r eliabilit y values ( ReliaSo f t , 2015 ). If the c onfi d e nce i nterval be t wee n two or m o re com pared gro ups o verlap, it can be concluded t hat t he diffe r ences b et ween t he groups were not si g nifi ca nt ( Cummi ng and Finch, 2005 ). The sev enth step was p l o tt i ng and co m par ing the overall reliabili t y v a lues in sc or ing go a l s (    󰇛  󰇜 ) of Ronal do and Messi based on CFM analysis. The eight o ne was in t erpret in g t he resu l t s of the stud y and d iscussing the compa r is o n of goal scor in g reliabili t y be tween Ro nal do an d Messi . Finally, t he last step was drawi ng conclusio ns based on the results and discussi o n s that were carrie d o ut bef o re. 3 Results 3.1 Overview of research data Table 2 provides dat a characteristics and go als distrib ut i on of Crist i a no Ro nal do and Li o nel Messi based on censorin g status and t he way s of goa l scored. Based on Table 2, it can be inferred t hat in every match he p layed, Ro nal do m anaged to score 0.72 goals , whil e Messi was sligh t ly higher at 0.80 goals/match. Moreover, R o nal do m a naged to score m o re t han 100 goal s t hrough 4 d ifferent ways nam ely through ri g ht- f oot ed kicks, lef t - footed kicks, penal t ies a nd head headers. On the ot her hand, l eft- footed kicks were t he only way Mess i scored m o re than 100 go als. Note t hat the numb er of ga mes p layed differs f r o m t he total data set analyze d, as a p l a yer might not score any goals, score o ne go al , t wo goals and so on f o r ever y game the y playe d. In addi t i o n to descri pt ive statis t i cs based on censoring status and t he way goals were scored, t he com pa r i so n of go a l dis t r ibution between t he t wo pl a yers is also pr esen t ed in m o re detail for each mi nut e of the games they p layed. Figure 1 describes the number of goal s scor ed by both players in ever y minute of t he game including t he ex t ra time. 5 Table 2. Data cha r acteris t i cs and goa l s d istr ib ut i on Var iab les Cr istiano Ronaldo Lionel Messi Frequency Perce n tage Frequency Perce n tage Numb er of ga mes P laye d 1,089 100.00 941 100.00 Status of censoring data Censored (did n ot sc o re a goal) 564 41.75 449 37.32 Unc enso red (scored a goal ) 787 58.25 754 62.68 Tot al dat aset analyzed 1,351 100.00 1,203 100.00 Way s of go als sc ored Penal t y Kick 137 17.41 99 13.13 Head Header 136 17.28 28 3.71 Direct Free Kick 57 7.24 57 7.56 Long Distance Kick 11 1.40 1 0.13 Ri ght- Foot ed Ki ck 303 38.50 92 12.20 Lef t - Footed Kick 143 18.17 477 63.26 Numbe r of games scor in g at l east 1 Goal 525 48.21 492 52.28 Figure 1. Distrib ut i on numbers of go a l s sco red ba sed on minute of playing A comparison of go al scoring reliability between Ronaldo an d Messi can be ma de by look in g at wh o had more goals in eve r y minute of t he game s t hey playe d. Tot al po ints earned by both players in ea ch minute of p l a ying are presented in Table 3. Table 3. Total po ints r epresen t the superi o r i t y in the number of goals b et ween Cr i st ian o Ronal do and Li o n e l Messi Superior Pl ay e r Minutes of Playing 1 - 45 46 - 90 91 - 120 Points % Points % Points % Cris t i ano Ronal do 19 42,22 22 48,89 7 23,33 Li o ne l Messi 19 42,22 19 42,22 4 13,33 Draw 7 15,56 4 8,89 19 63,33 Tot al 45 100,00 45 100,00 30 100,00 Based on T able 3, it is known that overall Ronaldo mana ged to gain 48 po in t s, or 6 poin t s m o re t han M essi. 3.2 Reliabilit y compa rison in scoring g oals between Ronaldo and Messi Figure 2 presen t s t he Kaplan Meier r eliabili t y curves of scorin g r eliabili t y f o r C ristiano Ro nal do an d Li o nel Mes s i b ased on 6 ways of go als sco red. 6 Figure 2. Ka p lan Meier reliabili t y curves for pena l t y kick (A), head he ader (B), direct free ki ck ( C), l o ng-range k ick (D), right- f o o ted kic k (E) and lef t - footed ki ck (F) While t he Log rank test resul t s are presen t ed in Table 4. Table 4. Lo g rank test on Kap lan-Meier reliabili t y cur ves of Cris t i a no Ronaldo and Li o n el Messi Ways of Goals Sco r ed Chi-square statistics p-value Penal t y kick 0.90 0.300 Head hea d er 0.00 0.800 Direct free kick 0.40 0.500 Long-range k ick - - Ri ght- f o ot ed kic k 0.50 0.500 Lef t - foot ed ki ck 0.50 0.500 Based on Fi gure 2. A, it is k nown tha t t he reli a bili t y curves of Ro naldo and Mess i in scor in g goa l s thro ugh Penal t y kicks overlap w i t h eac h ot her starting f r o m t he f i r st minute of the game they p layed to t he 50s. Al t h o ugh t he re liabili t y cur ves l oo k sli ght ly d ifferent especially in t he 50s to 90t h mi nut e t im e in t er val of the games t hey played, t he l o g ran k t est p ro ved that the diff erence was not si g nificant since p-value of the test was higher than the significance level of 0. 05 (Table 4). Figure 2.B shows that Ro nal do and Messi's r eliabili t y curves f or goals s cor ed using hea der s in t ersect each o t he r in many o bservation t im es, starting from the first minute of the game they played to t he 110th mi nut e (extra time ). T his resu l t was reinf o rced t hrough L o g Ran k test in g which sho wed t hat t he reliabili t y cur ves of the two pl a yers w ere not si g nificantly diffe r ent. Al t h o ugh the reli a bili t y cur ves for the di rect free ki ck in Figure 2.C appeared to be separate, further test ing proved that the diffe rence was not si g nificant. On t he other hand, the reliabili t y cur ve f or goal s scored fro m long-ran ge k ic k s (Figure 2.D) looks sl ight ly different f ro m the ot hers. The obs ervations f o r bot h pl a yers di d not r each t he 90t h mi nut e of t he normal time. Thi s was due to t he f act t hat nei t her Ronaldo nor Messi 7 scored any goal s t hrough long-ran ge kicks above t he 60th minute of the ga m e s they play ed. In addition, Messi's reliabili t y curve l o o ks ve r y simple and only takes t he f o rm of a ladder. This was because the number of goal s scored by Messi through l o n g-r ange kicks was o nly 1 goa l . Meanwhile, R onal do was able to sco re 11 g o als through l o ng-range ki ck s dur in g his 17 ye ars of career. Even so, t he numbe r of o bs ervations in t his analy s is wa s very small, es p ecially for Messi a nd did n o t all o w further analysi s thro ugh the Log Rank t es t . Ronal do a nd Messi's reliabili t y curves f o r g o als scored usin g r ight- f o ot ed kic k s (Fi gure 2.E) appear to o ve r l ap alm o st thro ughout the observati on t im e, st art in g fro m t he fi r st to the final minut e of t he game t hey p layed. This was in line wit h the resul ts of t he Lo g Ran k t est (p-val u e m o re than 0.05). Fin a lly, al though t he reliabili t y curves for l eft- f o ot ed ki ck s of both ke y playe r s seemed to be separate ( especi a lly in the span of 15 and 60th min ut es), f ur ther t es t ing pro ved t hat t he reliabili t y curv e s of t he t wo pl a yers (Figure 2.F) were not si gnif ican tly different. It sh o ul d be noted t hat, b ased on the resul ts of the p revious reliabili t y analysi s (Figure 2.D) , it is kno wn t hat th e number of goals scored by both pl a yers t hrough l o ng-range k i cks wa s limi t ed. Therefore, the CFM a nalysis in this study onl y considered t he reli ability values of 5 ways of sco rin g goa l s, namely t hrough penal t y k ick, head header, di rec t free k ic k, r i g ht-footed ki ck a nd l e f t- foot ed ki ck. T he C FM reliabili t y value of each player is s imply t he m u ltiplicat i o n of t hose fi ve reliabili t y values of the ways go als sco red. Figure 3 presen t s the CFM reli a bili t y curves f o r Cr i st iano Ronal do and L i o nel Mess i along wi t h i t s 95% confidence in t ervals. Figure 3. CFM reliabili t y cur ves of Cr istiano Ro nal do and Li o ne l Mess i The CFM reliabili t y curves for t he two playe rs in Figure 3 are sh o wn by different colors, bl ue f o r Cristian o Ro nal do and red f or Li o nel Messi. Th e con t inuous li ne sh o ws the C F M reliabili t y value, an d t he dashed l ine shows t he 95% conf idence in t er val . B a sed on Figure 3, it is kno wn that R onaldo and Messi's CFM re liability cur ves a nd i ts confidence i nter vals overlap with each ot her alm o st throughout the observ at i o n time, starting from the firs t m inute of t he games they played to the en d of the extra tim e (120 minutes). In line w i t h t he Ka p lan Meier reli a bili t y curves for each way of goals scored, the CFM reliabili t y cur ves f o r t he t wo playe r s also did not differ si g nificant ly bas ed on Cu mming and Finch's co nf ide nce in t er val criter ia. 4 Discussion The o bj ect ive of t hi s stud y was to compa re the level of reliabili t y in sco rin g goa ls between Cristiano Ronaldo and Li o ne l Messi dur in g m o st of their prof essional careers as f o o tballers. T he current study thro ugh CFM expl o ra tor y analys is sh o wed that Cris t i ano Ronal do and L i o n e l Messi had t he sa me reliabili t y in scor ing goal s in thei r golden era starti ng f r om t he 2002-03 season to the 2020-21 season. The recent st udy is in li ne w ith a st udy con ducted by Ande rson et al. (2020) who stated that voting f o r the b est soccer playe r in t he wo rld ( i . e. The Ballo n d’Or) was t i ght, es peci ally in 2016. While Messi rece ived a hi g her percentage of t he fi r st plac e vot es c o m par ed to Ronal do (24 . 1% vers us 23.1%), Ronal do achi e ve d highe r av erage po i nts com pared to M essi on the second pl ac e v o t es ( 1.78 poin ts ve rsus 1.73 p o in t s). However, there are ot her s t udies t hat favored Messi m o re than Ronal do or vi ce versa. Hussaini (2021) argued that Messi was the fi r st an d bes t pl a yer in t he worl d, whi le Cr istian o Ronal do was the 6th b est play er in the world us ing the 2021 FIFA Ba ll o n d'Or sta tist i cs. On t he ot her ha nd, Salv ado r et al. (2022) st ated that Ronal do was in t he first ranking while Messi in t he second based on dat a of the 2019/2020 s eason. Interestin g ly, a s t ud y by Grbec et al. (2024) usin g longer per i ods of dat a showed t hat bot h were n ot even i ncluded in top t en r ankin g. In t hei r study , Ronal do was in t he t welf t h pos i t i o n, while Messi was in t he top 14. The diff erent i at i o n am o ng t he m ent i o ned stud ies was due to the div er sity of t he seas o ns evaluated, m et hods empl o y ed and factor s i nvest igated since so far t here was no standard approach to m e asure t he perform a nce of a f o ot ball er. A st udy by Aror a (2024) rev ea led d iff ere ntiation of skill s and ro l es of Ronaldo and Mess i on t he pitch. Messi h as been well-known f or hi s pl a ymak in g, visi o n , and dr ibbling pro wess. His lightning-fast di rect i on c ha nges and i llustrious lef t f oot h ave been so dangero us f or t he opponen t s on the pi t ch. Messi c reated opport uni t i es a nd sco res goal s by playing as an o ffensi ve midfi e lder or forward. On the other hand, Ro naldo has bee n known for hi s fi n ishing, aer ial abili t y , and p hysicality. H is quic k ness, agili t y , and heading pro wess has made him a v ersat il e f o rward w i t h an excellen t goal scor ing abilit y. Whil e Messi was often praised for his natura l skill and co nsi st ent pl ay, Ronal do was praised for his dedicat i o n, wo rk ethic and versat ili t y across a range of leagues. Both R onaldo and Me ssi h a ve ac hieved un pre cedented success, be co mi ng global icons an d set t in g numer ous rec o rds. Thes e ind ividual a nd tea m ac hievements show t hat both were the m o st promi ne nt playe r s in the m o dern era of fo otball , where the quali t y of both was qu ite equal but far above other pl ayers around the wo rld. Ho weve r , both had different charac ters in terms of thei r scor in g st yl es where Ronaldo was m o re domi na nt in s coring go als with his r ight f oot, whi le Messi w i t h hi s l e f t f o ot ( Lam a & Praveen, 2017 ) . Yuw o no an d Rachman (2021) mentioned t hat t he kicking po wer of a foot ball p layer is si g nificant ly re lated to his traini ng m et hod and leg strength. Uniquely, Ronaldo h as a s pe cial t echnique ca lled knuckling shot in do ing free kicks ( Ho ng et al ., 2012 ). Al t h o ugh it l o o ks easy , sco rin g go als through penal t y k icks requires a str ong m e nta li t y and hi g h se lf - confidence ( Mardhika 8 & D imyat i , 2015 ). Our study re vealed that more th a n 17% of the go als scored by Ronaldo and 13% of t he go als scored by Messi over t hei r 17- year career ca me f ro m pe nal t y kicks . This pro ve d t hat both h a ve a goo d m e ntali t y and high co nfiden ce in executin g penal t y k icks. Furt herm o re, both were equal ly ad ept at sc o ring f ro m d i rect free k icks. Around 7% of t he tot al go als scored by bot h p l a yers o ver more t han the i r 17 - year pro f essional c areers c a me fro m direct f ree ki ck s. H o wever, Ronal do had a bett er accuracy rat e in scor in g g oals through hea d ers ( Mu mi n in, 2015 ). The data revealed t hat 17.28% of Ronal do ’ s goals were created by his h ead, while Mes s i o nl y scored 3.71% of his tot al goals through heade rs. Both players also had the highes t number of s hots on goa l per game of a ny player in t he wor l d in the last two decades. Messi had 6.1 sh ot s per gam e, while Ronaldo had 6.8 sh o t s/game ( Mazurek, 2018 ). Note t hat min ut es played, go als scored, assi st s scored, and t i t l es won ha ve a si gnif icant p o sit iv e infl u e nce on a f o otball p layer ma rket val ues ( Herberger & We d lich, 2017 ). Accord in g to Tran s fermarkt databas e, Ronal do reach ed the hi g hest market value when he p l a yed f o r Real Madrid C. F. at € 120 . 00 mi llion in 2014, 2015 an d 2018 at ages of 29, 30 and 32 yea r s ol d ( Transfe r markt , 2022b ) while Messi ac hiev ed the peak of m arket val u e at € 180.00 milli o n in 2018 at age of 30 years when he played for FC Barcel o na ( Transf ermarkt , 2022a ). In anot he r st udy , Mazurek (2018) t ri ed to i de nt if y a fi gur e that bears m o st r esembl a nce to Mes s i . His fi nd ing was surprising t hat Phili ppe Co utinh o , a Brazili a n f oot ball er t ha t playe d with him at Barce l o na during 2018- 2021 seasons was identifi e d as t he m ost resemblanc e to Messi . In add i t ion , t he study also ident ifi ed P ierre-E m er ick Aubameyang, now playing as capt ain of t he Gabon national tea m , as t he most simila r fi gur e w i t h Ronaldo usi ng a dat aset f ro m the 2017/2018 seas on. U nf o rt unately , bot h Co utinh o and Aubamey a ng we re not in cluded in t he to p 20 pl a yers based on dat a of t he 2000/2001-2022/2023 seasons ( Grbec et al ., 2024 ). Mor e complex a nalysis for det ermi n ing the best seas o n and career of a football er ca n be done us ing t he ModK f o r mula pro posed by Salvador et al. (2022) . However, a lot of fa cto rs nee d to be considered in t he f or mula. It in c ludes individual indicators in national tea m s a nd clubs, in d icator s of ga mes and titles in national t eams an d clubs, the im pact of the athl et e on national teams and c l u bs, and also t he usage of point s per m at ch ( i .e. t he ave r age po in t s earn ed durin g the presence of the athlete in t he team). Sar m e nto and A raú j o (2020) stated that an ex pert perf o r m ance and high achievement of a football pla y er emerge f r o m circumstances r esu l t i ng from t he self - or ganiza t i o n of several p er f or mers-envi ro nmenta l facto rs. Ronal d o and Mess i are indisputable examples of ide al foot ball p layers who have fulfilled a ll requirements (e.g. s peed, strength, agi lit y, enduranc e, men ta li t y, etc.) to be the b est am ong others. It is not surprising that t he current study proved that b ot h playe r s had simila r consistency in scoring goals in m ost of their pro f essional careers as football players. Finally , Clegg and Robinson (2022) argued in t hei r boo k that t he dis cus sion of “ Ro naldo or Messi ?” f o r milli o n s of people around t he g l obe is not simply a barr oom argum e nt or an affirmat ion of fando m , b ut ra ther a phil o sophica l stat ement. Indeed, t he phil o sophical debates may have contributed to t he comme rcializat i o n of f o otball, b ecause t he t wo play ers h ave likely driven si g nificant c ommercial i ntere st and reven ue for clubs, leagues , and brands. As a result f oot ball st rengthen i t s global reach w i t h t hes e two icon playe r s in t urn ins pir ing new y o ung football p laye r s at tract ed by t he va lue and image of g l obal f o o tball t oday, and perhaps m o t iv at ed to shape the future of f o o tball . There are sev era l limi t at i ons of t his st ud y t hat ne ed to be highlighted in c luding the absence of a stat i st i ca l method that all o wed the researchers to c o m par e the CFM re li a bili t y curves of Cristian o Ronal do an d Li o nel Messi. To overco m e t his limi t at i o n, we ut ili zed confidence interval t heor y approach to draw con cl us i o n s from t he CF M an a lysis. Furtherm o re, other factor s havi ng t he pot ential to aff e ct the per form a nce of the playe r s w ere a lso not i ncluded in the analysis due to da t a limi t at i o ns, suc h as phys ical fi t ness while playing, post-injur y conditions , m at ch i mport ance an d home/away st atus. In addition, Ro nal do an d Messi did not al wa ys play in t he sam e compe t ition. Fo r exam p le, dur in g t he r esearch per io d t hey o nly playe d in the s a me league when Ro naldo defen ded Real Madrid C.F. and M essi playe d f o r FC Barcelona in the Spanish La Li ga f o r t he 2009 -10 to 2017- 18 seas o ns. Neve rt hel es s, examining data f ro m the 19-y ear career of Cristiano Ronal do as professi o nal foo tball p layer and 17- ye ar career of Lionel Mess i are beli e ved to be able to pr o vi de significant inf o r mati o n regarding the com par ison of t he sc or in g re li abilities of t wo extraordinary players in t he modern football era. 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