Cristiano Ronaldo has been a prolific scorer and dominant force in England, Spain and Italy during his illustrious career. But how has his playing style altered as he has achieved success with Manchester United, Real Madrid and Juventus? Gab Marcotti dug into the data. (For his look at Lionel Messi's career, click here.)

Note: Statistics and data measured per 90 minutes via Opta and StatsBomb and based upon games played before the coronavirus-enforced shutdown of European football in March.

Jump to: Early years | Taking over | Peak Cristiano | Birth of a centre-forward | Life as a 30-something

The early years (2002-06)

Cristiano Ronaldo made his professional debut for Sporting at 17 years of age, coming on at half-time of a home defeat to Partizan in the UEFA Cup. You could tell he was not fully developed physically; he was tall and thin with a shirt billowing, and not just because that was the style at the time.

Sporting knew they had something special on their hands, but as often happens with young players, there was a fear of mental burnout. Plus, perhaps, a lack of clarity on how to best use him.

The focus was on Ronaldo's most obvious skills: speed in open spaces, long limbs pumping and an ability to beat opponents one-on-one. The rest was all to be discovered; he had played more centrally at times at youth level, but was used almost exclusively wide in the first team, as often happens with players breaking through.

Give him space. Let him breathe. Let him find who he is.

Most know the story about how Sir Alex Ferguson became determined to sign Ronaldo after he starred in an August 2003 preseason friendly between Manchester United and Sporting, but United had been tracking him for some time, and as best we can tell, that game didn't persuade Ferguson to sign the 18-year-old as much as it persuaded him to take Ronaldo to Old Trafford straightaway rather than leave him for a season on loan at Sporting.

United got his signature ahead of several other European clubs who had been hot on his tail, including Arsenal, Valencia, Barcelona -- yes, there's a parallel universe in which Ronaldo and Lionel Messi are teammates and monopolise the sport for 15 years -- and Parma, who had a verbal agreement with Sporting.

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The Ronaldo who arrived in England -- and inherited United's No. 7 shirt from Real Madrid-bound David Beckham -- was a close relative of the Sporting version. He was a piece of clay, yet to be molded but hungry to experiment. He was encouraged to express himself, and that usually meant one thing: dribbling and beating opponents.

His mazy runs usually started wide and took him all over the pitch, but his head was often down, and this meant he would miss the runs of teammates or fail to spot the moment to shoot. In fact, Guillem Balague notes in his biography of Ronaldo that when he was playing as a traditional winger, other United players were sometimes left frustrated: "Why doesn't he just bollock it!?!" Gary Neville used to think each time he would see Ronaldo take an extra touch and pass up the opportunity to shoot.

Centre-forward Ruud van Nistelrooy was among the most irritated, running into space for through balls that never arrived and losing defenders for crosses that never came. Going from Beckham to that version of Ronaldo was not easy when you were a supply-dependent striker.

Ronaldo's Premier League statistics from that period are limited to goals and assists, but they corroborate the idea that he was a work in progress. H e averaged 0.2 assists and 0.26 non-penalty goals, which are not bad numbers for his age, but they did not offer many clues to what would happen in the next stage of his development.

We do have more detailed statistics -- albeit with a smaller sample size -- for his performance at Euro 2004, where he was a 19-year-old who parachuted into the final years of Portugal's Golden Generation. Ronaldo attempted more dribbles (7.79) than anybody else at the tournament and ranked among the leaders in shots on goal with 4.1.

Tellingly, and unlike most of his later career, he was also among the tournament leaders in possession-adjusted tackles and interceptions (3.29). Being on the big stage, with the pressure of playing for a host nation, perhaps gave him more freedom than he found at United, where he joined a veteran side coming off years of success.

Taking over (2006-09)

In the summer of 2006, United made what would turn out to be a fateful decision, selling Van Nistelrooy to Real Madrid and clearing the way for the further development not just of Ronaldo but also of Wayne Rooney, another young attacker born in 1985.

Van Nistelrooy, who had just turned 30, had notched 150 goals in all competitions during five seasons, but rather than replacing him directly, Ferguson went into the 2006-07 season with an attacking corps, the members of which all had questions to answer.

There was Rooney and Ronaldo, respectively just 20 and 21, plus 33-year-old Ole Gunnar Solskjaer, who had not started a league game for two years, and Louis Saha, no stranger to the treatment table himself and scorer of just 24 goals in two and a half years at the club. Alan Smith was also there, but had suffered a bad injury the previous February and was not exactly a scoring machine, as evidenced by one goal in his previous 33 outings.

United had failed to win the league in each of the three previous seasons -- the club's longest drought in 15 years -- and had finished an average of 14 points outside first place in that time. Their only new signing ahead of the 2006-07 campaign was Michael Carrick, a deep-lying midfielder; essentially, Ferguson was handing the keys of the team to Ronaldo and Rooney.

Ronaldo became the focal point of the attack, or, rather, because Rooney was also an unorthodox striker rather than a traditional centre-forward, the pair were the hub of a fluid offense, each reacting to the other's movement. Ronaldo began to exploit his aerial ability, scoring eight league goals over three seasons with his head and vastly outperforming expected goals -- xG -- which amounted to 3.03 in that time.

He usually lined up on the right, but occasionally played through the middle or on the left, but in some ways where he started mattered less than where he ended up: all over the pitch, creating mismatches and wreaking havoc. As he took on more attacking responsibility, he started taking more shots and averaged more than five a game, a figure he would stay above through the rest of his United career.

Not only that but, to use Neville's term, he started "bollocking it" from distance. Of the 527 shots Ronaldo took in those three seasons, nearly 60% came from more than 21 yards out. That would remain a hallmark throughout his career, although his effectiveness from distance has waned over time. So too has his dead-ball prowess; in this period, he scored nine free kick goals in the league.

To accommodate Ronaldo's freedom, Ferguson added attacking players in 2007 (Carlos Tevez) and 2008 (Dimitar Berbatov). While both helped share the load, crucially neither was a traditional centre-forward who might clog the middle or get in Ronaldo's way. Tevez, a bit like the Rooney of the time, was a hardworking, unselfish force of nature, and Berbatov, while offering less in terms of work rate, liked to find space deeper and often prioritized finding teammates over scoring himself.

United won three consecutive league titles and, just as important, excelled in the Champions League, reaching a semifinal and two finals (winning it all in 2007-08). Over the past 50 years, the club have reached the final four of the Champions League or European Cup on only five occasions: three of them came in this period, with Ronaldo running rampant.

While this piece is mostly about his individual statistics and how he has changed and evolved, you cannot forget that football is a team game. And it is not a coincidence that his last three years at United, when he was tasked with carrying the team, coincided with arguably the best three-year period in club history.

Peak Cristiano (2009-14)

But for Ferguson's veto and a gentleman's agreement, Ronaldo would have moved to Real Madrid in the summer of 2008. Instead, he made the switch a year later as part of perhaps the biggest (and most expensive) overhaul in history. In addition to his world-record fee of €94 million ($102m at the time), Kaka, Karim Benzema, Xabi Alonso and Raul Albiol also moved to the Bernabeu as part of a quarter-billion-Euro spending spree for new manager Manuel Pellegrini.

Florentino Perez's return as president heralded a new "Galactico Era," following that of Zinedine Zidane, Luis Figo and the original Ronaldo, but the learning curve was steep. Cramming so many stars, plus a number of illustrious holdovers, into a coherent XI was not easy for Pellegrini, and the task was made harder by the fact they were up against Pep Guardiola's Barcelona.

Real Madrid finished second in 2009-10 but were a disjointed side that crashed out of the Champions League at the round-of-16 stage. That they ranked last in La Liga for shot quality, with an xG/shot of 0.06, tells you this was more a bunch of individuals than a team.

Ronaldo took responsibility, as he had done at United. He led the team in shots and dribbles attempted, and his time was divided quite equally along the attacking front: left, right and centre. He finished the campaign with 33 goals; 26 of them were scored in La Liga, which saw him one behind Gonzalo Higuain.

Things changed when Jose Mourinho replaced Pellegrini. The relationship between the Portuguese pair would go through highs and lows, but the "Special One" quickly found Ronaldo a clear position as a left-sided wide forward, with plenty of licence to come inside. He still took plenty of shots (averaging 6.91 over Mourinho's three seasons), but took them from better positions (his xG/shot doubled to 0.12).

Mourinho's approach was less possession-based than that of Pellegrini, and Ronaldo thrived with greater reliance on quick transitions and playing into space, while quickly adapting to Higuain and Benzema, who alternated at centre-forward.

Higuain was more of a penalty-area striker, but had the technique and vision to set up wingers and midfielders for shots. Benzema, a bit like Tevez and Rooney at United, covered huge areas of the attacking front, running tirelessly and allowing Ronaldo to pick his spots. The two would form a devastating tandem for most of the next decade.

Ronaldo was still very much in the limelight, but an outsized personality like Mourinho, who would often willingly act as a lightning rod for the media, shifted some attention away. Ronaldo's personal life was more settled too: He was in a stable relationship and lived with his mother and children. As he entered midcareer, he became more preoccupied with preserving his body and getting the best out of it.

Working with Valter Di Salvo, Madrid's fitness coach, Ronaldo developed and embraced an all-encompassing program that covered not just conditioning but also nutrition and sleep. Everything was tracked, from crumbs of food to minutes of recovery. It was during this period that he also bulked up, adding muscle to his frame.

His game became more essential, more direct, more functional. His attempted dribbles declined annually, from 6.26 in 2009-10, to 3.93 in 2012-13, Mourinho's final season. By contrast, his scoring really picked up: Ronaldo averaged 30 goals from open play in the league during Mourinho's three seasons.

The 2012-13 campaign was also telling in terms of his role as a leader. A stressed Mourinho went to war with media, players and opposing clubs as Madrid finished 15 points behind Barcelona, and Ronaldo, who had previously led mostly by example, became an important voice in the dressing room. He stood up for his teammates and had no qualms about confronting his manager, which was not something to be taken lightly, given they shared the same agent, Jorge Mendes.

The summer of 2013 saw the arrival of Gareth Bale, whose fee was slightly higher than that of Ronaldo, although the club made it part of his contract for that not to be made public. Ronaldo remained the team's centrepiece, with Bale adapting to the opposite wing. New manager Carlo Ancelotti, as per his modus operandi, tried to retain parts of Mourinho's setup while adding his own tweaks.

The idea was to give Bale, Benzema and Ronaldo -- the trio would soon be known as "BBC" -- even more freedom. Mesut Ozil, who had been one of Ronaldo's regular assisters when operating in the hole, was sold to Arsenal, while Higuain went to Napoli, turning Benzema into the full-time centre-forward.

Ronaldo became even more of a fixture in the box -- for the first time in his career, he shot more from inside 21 yards than outside -- and his attempted dribbles increased. The BBC were supported by a hardworking midfield of Luka Modric, Angel Di Maria and Alonso, and that combination helped, in May 2015, lead Madrid to a long-awaited Decima, the club's 10th European Cup.

Birth of a centre-forward (2014-16)

Ronaldo was arguably enjoying the best season of his career in 2013-14 -- by the midpoint of the Liga season he had scored 22 goals, plus another nine in the Champions League -- but patellar tendinitis in his knee flared up again and would not go away. He missed several weeks in February and April, plus another three in May, before rushing back for the Champions League final.

He insisted upon playing through injury and his production remained consistent, but he was struggling and would continue to do so at the World Cup, where he scored just once as Portugal went out in the group stage.

As he worked his way back in 2014-15 -- very much a "playing rehab" as he missed very few games -- his body began to change again. The chiseled features remained, but he started to shed weight, turning leaner. Part of that was to give his knee some relief, part of it was to best exploit some of the mismatches coming his way.

Ronaldo gradually became a de facto centre-forward, too physically strong for most full-backs but still quick enough against most central defenders. It was not an overnight process, by any stretch. In 2014-15, he attempted just 3.62 dribbles, the lowest total of his career, and was successful less than half the time (1.8).

The knee, evidently, was still bothering him, and this could also be seen in his work off the ball. He had never been the most hardworking when out of possession, but in 2014-15 he recorded 0.34 possession-adjusted tackles-plus-interceptions every 90 minutes, ranking dead last in La Liga.

But he moved very much like a centre-forward when Madrid had the ball. Remember how nearly 60% of his shots came from beyond 21 yards during his later United days? Now the proportion was reversed and nearly 60% came from inside the area. His finishing ability and knack for anticipating defenders made all the difference, and he ended up with a monstrous 48 league goals (61 overall) in 2014-15, of which a career-best 38 came from open play.

The trend continued the next season under Rafa Benitez, with whom he clashed and of whom he was harshly critical after Benitez was sacked in January 2016. They clearly did not see eye to eye, but that did not stop Ronaldo putting together another impressive season statistically, in part because he was finally fully fit.

He scored 29 league goals from open play, while maintaining his shot volume of nearly six and logging shot quality of 0.14 xG/shot. He had refined his movements in the box, further developing an already keen sense of where the ball was going to go.

Ronaldo continued to dribble less relative to earlier seasons, mainly because he was operating so close to goal. He scored 16 times in Europe, and after Zidane replaced Benitez, Madrid won the Champions League in May 2016. It looked as if Ronaldo's purple patch was set to continue.

Life as a 30-something (2016-present)

Ronaldo finally won a major international tournament when Portugal upset France in the final of Euro 2016, but he was forced off after 25 minutes with injury, and the aggravated knee issues caused him to miss not only the preseason but the opening weeks of the club campaign.

The next two seasons at Madrid felt as if the club was intent on winning while the window of opportunity was still open, and with a mostly unchanged cast, they reached and won two more Champions League finals to make it three European Cups in a row, while also finishing top of La Liga in 2016-17.

By this stage, Ronaldo was in his early 30s and, along with many of his teammates, relied on guile, technique and experience more than athleticism. As a team, it often felt as if they were on cruise control, simply raising their game when they needed to. Which is what you expect from a veteran side.

Ronaldo fit this new ecosystem. In 2016-17, he scored 19 league goals from open play, his lowest total since arriving at the Bernabeu; the next year he had 23, his third-lowest mark. His shots went down to 5.88 over the two years, lower than in any season since joining Real Madrid.

Moreover, he rarely dribbled (2.39 attempts) and, when he did, was not particularly effective (successful just 0.99 times). Similarly, he rarely shot from distance, with an average of 43.5 attempts per season, fewer than in any single campaign over the previous decade. He was ineffective when he did let fly, scoring just three times.

It was not necessarily a decline, especially looking at the overall numbers and his ability to perform when it counts. The 86 goals in all competitions over those two years was a total second only to Messi's, and his leadership remained unquestioned and he regularly popped up at crucial times.

Witness his performances in the 2016-17 Champions League knockout phase: five goals over two legs against Bayern Munich in the quarterfinals, a hat trick against Atletico Madrid in the semis and two against Juventus in the final. That year, he also scored five goals in Real's last five Liga games, all of them wins that saw Madrid bounce back from defeat to Barcelona in El Clasico to win the title by a nose.

The next year, he scored five times in the Champions League knockout rounds, with Paris Saint-Germain and Juventus among his victims. At the World Cup, his opening-game hat trick against Spain served as another reminder of what he could do on his day.

Portugal went out at the last-16 stage, after which Ronaldo moved to Juventus. He was 33, and with hindsight it is hard to overstate the transition he had to make after nine seasons with the same club. It was not just about adapting to Serie A but also about fitting into a team that had been very successful domestically, playing in a way that was not necessarily suited to his skill set.

Real Madrid under Zidane and Juventus under Max Allegri in 2017-18 were very different animals. Madrid took 4.2 more shots per game; their xG was 30% higher; they pressed far more and created more chances off the press. Allegri was tasked with making Juventus' style fit Ronaldo while also delivering results.

It was far from straightforward, so perhaps it should not come as a surprise that many of his numbers declined further, a trend that has continued in the current season. Maurizio Sarri replaced Allegri and in theory -- as a more attacking manager willing to commit more players forward -- should have been a better fit for Ronaldo.

However, after five years under Allegri, the entire team found the transition difficult, and Sarri struggled to get his new squad consistently playing the way he wanted. In hindsight, announcing early in the season that Ronaldo "didn't need to worry" about tactical instructions but rather the rest of the team would work for him, might not have been a great idea by The Old Lady's new boss.

That combination -- an unsettled team, managerial change, a philosophy that deviated from the Real Madrid ethos -- has not been easy for Ronaldo to navigate.

Ahead of Serie A's shutdown in March, his non-penalty goals (0.50 last year, 0.60 this season) were down to levels not seen since his final year at Old Trafford; his shot totals dropped (5.36 and 5.44); and his xG (0.60 and 0.48) dipped to levels not seen since his first season in Spain. His proportion of shots from distance was in line with the previous five seasons (37.7%) but he scored very infrequently from range: one goal in 112 attempts for Juve came from beyond 21 yards.

His touches in the box, on the other hand, are way up (8.44 last season, 13.43 this year, which is higher than ever for him, bar one year at Madrid). That suggests his teammates are determined to find him but, perhaps, do not necessarily get him the ball where he can hurt opponents as often as in the past.

It is difficult to divorce Juventus' style of play, upheaval in personnel and managerial change from Ronaldo's own performances, and there is no question that this is a different player who, perhaps understandably as he ages, is not hitting the superhuman levels of past seasons.

The question is how he will adapt to this "new normal" and whether, when (if?) Juventus have their upturn, he will click back to something close to what he was in his guise as a right-sided centre-forward or will reinvent himself again or whether, in his mid-30s, Father Time is finally catching up with him.