Manchester United legend Ryan Giggs opined that Cristiano Ronaldo's possible obsession with being better than Lionel Messi may have motivated his decision to dump Real Madrid for Juventus. The 33-year-old Portuguese has won both league titles and champions league in both England and Spain, winning his first Ballon d'Or during his time in Manchester. However, Messi has spent his whole career at Barcelona. Ronaldo brought down the curtain on his nine-year spell at the Bernabeu as the club's all-time leading scorer, with 450 goals in 438 games. He also won the Champions League four times, three FIFA Club World Cups and two La Liga titles, as well as the Copa del Rey and Spanish Super Cup twice apiece. Ronaldo and Messi have battled to be deemed the best player in the world. The duo have each won five Ballon d'Or awards over the last decade, winning five Ballons d'Or apiece as Real Madrid and Barcelona fought for supremacy in LaLiga. Giggs, who starred alongside Ronaldo in the Premier League with Manchester United at United when he lifted the first of his five Champions League titles, believes Ronaldo's obsession to prove himself as the world's best could be spiced up his desire to move to Juventus and conquer Italy. "I'm surprised that he would leave Real Madrid and go to Italy," he told ITV Sport. "I think it's a big challenge for him but he's going to a huge club. Having that on your CV... Real Madrid, Man United and Juventus. It's some CV. "He's obsessed with being better than Messi. He has that now that 'I did it in England, I did it in Spain, I'm going to do it in Italy... and I did it with Portugal'. So maybe that will be his argument when people ask: 'Is Ronaldo better than Messi?'." Ronaldo has featured and starred for three different clubs, Juventus will be his fourth professional club, while Messi looks unlikely to leave the Camp Nou in the near future although the 31-year-old has previously spoken of his desire to play in his native Argentina. While some people sees it as a edge over Messi, below is a list of players that played their entire career at a club, does it take anything from them? Lev Yashin Lev Yashin who is regarded by many as the best goalkeeper of all time, played his entire 22 year career at FC Dynamo Moscow. Paolo Maldini Arguably the greatest left-back in the history of the game, he made 647 league and helped his side to seven Serie A titles. Tony Adams Tony Adams spent his entire 19 year career, at Arsenal, captaining them for 14 of those years with great distinction. He was one of the best English football has ever seen. Thanks to him, Arsenal lost just once in the 1990-1 season and earn a reputation for being nearly impossible to beat. Carles Puyol Carles Puyol is one of the best defenders in history, hr was even named European right-back of the year in 2002. Ryan Giggs Giggs himself spent his entire career at Manchester United making 613 league appearances to became of the greatest winger of all time. Paul Scholes When Paul Scholes retired, Zidane said, "Scholes is undoubtedly the best midfielder of his generation." Zidane is in that generation, and he is one of the all time greats. Steven Gerard Steven Gerard, did exceedingly well for Liverpool to became one of the club's greatest The list goes on and on and on.