Chelsea and Manchester City players were reportedly involved in an altercation after their Premier League clash at Stamford Bridge on Monday evening.It has been suggested by City boss Roberto Mancini that Chelsea players, high on emotion after a crucial win which reduced the gap at the top of the table to seven points, and in particular Ashley Cole may have been at the centre of the incident.When asked what had happened, Mancini said: "I don't know if Cole said something. I don't know what he said. I don't understand. But if the Chelsea players are saying we are a top team, for us that is important. There were really lively because they beat a top team. It's normal. It's important for them."Blues boss Andre Villas-Boas denied the claims about Cole, saying: "It is untrue, it is unfair. There is always some troublemaker in our wins."Mancini also took the chance to take a sarcastic swipe at referee Mark Clattenburg's performance, with a series of questionable decisions including Jose Bosingwa's tackle in the box on David Silva not being adjudged as a foul. Chelsea were given a spot-kick for a handball by Joleon Lescott while Gael Clichy was sent off for two yellow cards."I agree with all of his decisions,'' Mancini said. "There was a big penalty. There wasn't a fan inside the stadium who didn't see it. But the referee was very close and he didn't."I don't know (about Chelsea's penalty). The Chelsea player shot very hard from five or six metres. It is difficult for the defender. But, at that moment, the referee was really sure. It was after the sending-off, that the game totally changed."It doesn't change anything for us, because we knew before this we should lose a game at some point. It is unusual that a team comes to Chelsea and plays like we did in the first half because we dominated the game. We didn't deserve to lose but we did."The season is very long and very hard. Now we should prepare for another difficult game, against Arsenal.''Meanwhile, Mancini said he will take no action against Balotelli for breaking a 48-hour pre-game curfew by going for a curry in Manchester on Saturday night.