City's playmaker, a star man for them so far this season, left the field clutching his back in the second half before his side recorded a Group A victory at El Madrigal. However, manager Mancini said afterwards he was not concerned. He said: "I don't think this is serious. He took a knock on his back. "Also we play again in 60 hours against QPR. I think he can recover well." Meanwhile, Mancini believes City can look forward to their vital clash away to Napoli with confidence after sweeping Villarreal aside. Their hopes of progress were already likely to hinge on their trip to Naples later this month but now they have a two-point advantage over the Italians, victory will make certain. Mancini said: "I think this win is important because now we have a good chance. "We know that everything will be in Naples. "I think it will be an incredible atmosphere. There will be 70,000 people at the stadium. "I think it is very difficult to play but it is important to go there with this result. "I don't think it was easy to win here but we played very well and after the first goal it was easier. That was really important." Yaya Toure struck twice for City either side of a Mario Balotelli penalty. City needed to be patient as Villarreal looked to press them early on but once Toure had opened the scoring after 30 minutes, the result was rarely in doubt. Mancini added: "Villarreal were missing four or five important players but it is always difficult to win away in the Champions League. "We had 65 per cent of ball possession, we scored three goals. I think this was important for our confidence. "I think we have improved, not just in the Champions League. "It is important for us to go in the second stage, then everything can happen with us because we are a good team. We can improve a lot in the next month." Mancini did not know anything about suggestions some of his players may have been a target for racist chanting. The Italian said: "I don't know this." Mancini was also unaware that someone may have been attempting to put Balotelli off by shining a laser pen at him as he prepared to take his penalty. The result left Villarreal bottom of the group without a point and ended their mathematical chances of progressing. The Yellow Submarine, who have endured a miserable start to their domestic season, were without a host of key players and were well beaten by the final whistle. Their under-pressure coach Juan Carlos Garrido said: "It was a very difficult game. "I want to congratulate the winners tonight. We all know this is a very hard competition. "But tonight, despite all our injuries, we never complained and I want to congratulate our players as well. They played very well despite the 3-0 scoreline. "This is the spirit of the team and I want to emphasise this. If we can go on with this feeling when we have these players back, we will have better results."
