Ruud van Nistelrooy was one of Manchester United's top hitmen in the early 2000s, and Cristiano Ronaldo reportedly played a huge part in the Dutchman's exit from the club.
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Spanish football expert Guillem Balague recently released a book on Real Madrid superstar Ronaldo, and in it he touched on the Portuguese player's relationship with Van Nistelrooy.
The Dutch forward's exit from Old Trafford reportedly had more to do with Ronaldo than most football watchers knew, according to Balague.
"As Ronaldo was still learning how to release the ball at the right time, those suffering the most were the United forwards," Balague wrote in his book titled Cristiano Ronaldo: The Biography.
"'I can't play with this guy. He doesn't even cross the ball,' Ruud van Nistelrooy would often shout in training. 'I can't make my runs because he's not going to cross the ball.'
"On a few occasions, Rio Ferdinand heard the Dutch striker say that he did not want to play with Ronaldo again.
"'I think Ruud was used to David Beckham crossing the ball every time he had it,' explained Edwin van der Sar.
"'David didn't have pace to dribble and beat opponents, so he had to do something else. Ronnie had the pace and the tricks.'
"Cristiano was a winger with a striker's soul, but there was also something else in that conflict, a more human element. Van Nistelrooy, who scored 150 goals in five seasons at the club, was United's big star when Cristiano arrived. All of a sudden, a thin, adolescent Portuguese trickster was winning over supporters.
"'They had a couple of arguments,' revealed Ferdinand. 'Ruud Van Nistelrooy kicked him one time and after that I kicked Ruud just to protect Ronnie a little bit and Ruud swung a punch at me and he missed.'
"That incident took place just before the final match of the 2005/06 campaign against Charlton. Cristiano started while Van Nistelrooy did not make the squad. The Dutchman would never play for the club again."
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Van Nistelrooy scored 150 goals in just 215 appearances under Sir Alex Ferguson at United.
Do you think United made a mistake by letting Van Nistelrooy leave in 2006? Let us know in the comments section below.