Cristiano Ronaldo trained so long and so hard as a youngster that his boss had to force him to stop and go home

• Cristiano Ronaldo had to be forced to stop training and go home by the manager according to a former teammate.
• Nicky Butt, who played with Ronaldo at Manchester United, said Sir Alex Ferguson had to order him to go home.
• Butt said you could hear Ferguson "bellowing across the training fields" that it was time to stop.
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Soccer superstar Cristiano Ronaldo used to spend so long practicing on the training field that legendary Manchester United manager Sir Alex Ferguson had to order him to go home.

Nicky Butt, a former United teammate of Ronaldo's, said that Ferguson used to shout at the future star after he would spend extra hours practising his skills while the other players ate lunch.

"​​He was the last to leave the building. In fact, you couldn't get him off the training pitch as he worked relentlessly on his techniques, as we were all walking off he was carrying a bag of balls to work on those techniques.

"We would be having lunch in the canteen or getting ready to go home and you could hear the voice of Sir Alex bellowing across the training fields at two or three o'clock in the afternoon, shouting at Cristiano that it was time to get off the pitch as 'we have a game in two days – enough now'!" Butt wrote in a foreword to a new book called "Viva Ronaldo! The Second Coming of Cristiano."

Ronaldo is famous for his relentless work ethic and it was recently reported that the 36-year-old's strict health regime was so intimidating that other United players skipped dessert during a pre-game meal.

Butt, who played 270 times for United, said Ronaldo's obsessive mindset was there from the start.

"Ronaldo was to emerge as a genius but it wasn't just his talents that took him right to the top.

"It is often said that certain players worked hard, stayed behind for some extra training or to practice their techniques, but with Cristiano it was total dedication, total commitment, and total hard work.

"He didn't have a god-given physique, it wasn't given, he worked hard to achieve it. He actually came to us as a skinny, scrawny young kid, and worked hard to get that physique over many, many years.

"We would also see him work relentlessly on his free kicks and he would tell us about something he had seen somewhere, and he wanted to perfect it, and he would work again relentlessly until he did.

Butt's story echoes one told by a former coach in a recent documentary about the star. Manchester United's former power development coach Mick Clegg told the documentary that as a youngster Ronaldo often trained alone behind a hill at the far side of United's training ground so that no one would see him make mistakes.