In an extract from his latest book, Spanish journalist Guillem Balague reveals Cristiano Ronaldo's bust-ups with Jose Mourinho and Alex Ferguson, and why he needed a mirror at the training ground. The tension was reaching breaking point in the Real Madrid dressing room. They faced Valencia in the Copa del Rey in 2013 and Mourinho's side were leading 2 - 0.Mourinho reminded Ronaldo of the need to track back "if they get a goal against us," he warned the Portugal forward.The player got up and began shouting: "After everything I've done for you, this is how you treat me! How dare you say that to me?"Mourinho was unable to contain himself any longer."Just so you know," he shouted for everybody to hear, "many think like me here, but don't dare say it, they don't have the balls to tell you."The situation escalated to the point at which Ronaldo had to be held back to prevent the pair from coming to blows.When he arrived at Manchester United, Ronaldo chose the locker opposite a mirror."He put up a 2m mirror," recalled Phil Neville.Quinton Fortune tells it differently: "We even put a mirror in his locker so he could have a look at himself."In a Champions League defeat against Benfica, Ronaldo spent the game trying to prove why he was a Premier League player and had a bad day.In the dressing room, Ferguson ranted: "Who do you think you are? Trying to play by yourself. You'll never be a player if you do this!"Ronaldo began to cry. The other players let him be."He needed to learn," said defender Rio Ferdinand...