Real Madrid coach Jose Mourinho has admitted his fears that the injury picked up by Cristiano Ronaldo during their 7-0 victory over Malaga in the Spanish Primera Division on Thursday evening could be serious.The Portugal international asked to be substituted immediately after scoring his third goal of the evening at the Bernabeu in the 77th minute, leaving his team to play the remainder of the match with ten men as Mourinho had already used all three substitutes.After the match, Mourinho revealed his apprehension that the muscle injury to Ronaldo could be serious and, according to the Canadian Press, said, "I don't know. It seems like a serious injury, that's the negative note from the game. Especially as Ronaldo doesn't just do small things.""If Cristiano has something it's something minor, it's no drama," Mourinho added.Update 0120 CET: Madrid's official website later confirmed that Ronaldo had suffered an injury to his left hamstring and explained the player's progress is being monitored.Source: Goal.com