It’s well-known that Manchester United’s players used to kick Cristiano Ronaldo in training in an attempt to toughen him up.

The Portuguese arrived at Old Trafford in 2003 with a great deal of talent but without much experience. And so United’s players decided to be rough with him.

"Ronaldo had a real tough time for the first two or three years when the manager tried to toughen him up,” former United midfielder Darren Fletcher revealed last year, via the Manchester Evening News.

"He kept on to the ball too long and he wasn't delivering it into the box he was beating men two or three times and his end product wasn't there.

"When he kept onto the ball he learned the hard way there's no doubt about that. He got kicked but that was the way of telling him, ‘if you do this you’re not helping the team and you’re going to get kicked in games.’”

United’s rough tactics clearly worked. With four Ballon d’Ors and three Champions League winner’s medals in his list of honours, Ronaldo is one of the greatest players in history.

Ronaldo: I learned the art of football at United

Those formative years, under Sir Alex Ferguson and surrounded by veterans in Fletcher, Rio Ferdinand, Paul Scholes and Ryan Giggs, were very important in Ronaldo’s career.

"Alex Ferguson was a father for me in football," Ronaldo said earlier this year, per Sky Sports. "I learned many things, not just from the coach but the players.

"I improved not just my skills but my body too.

"In the five years that I was [at United] I learned the art of football. It was a dream for me."

One United player couldn't take Ronaldo's stepovers

His flamboyant style didn’t please everyone. During BT Sport’s recent Champions League coverage, Ferdinand told a story of how the Portuguese’s excessive use of stepovers forced Ruud van Nistelrooy to almost leave the training ground.

“I remember Ruud van Nistelrooy almost walked in from training because he was doing about 50 stepovers,” Ferdinand said.

“He said, ‘I can’t play with this. Cross the ball so I can make runs to score goals.’”

It was all about finding the balance between putting on a show and helping the team to win. Once Ronaldo did that, he became a superstar.

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