Sir Alex Ferguson has backed Wayne Rooney in the row over his role in Manchester City skipper Vincent Kompany's controversial red card.
City boss Roberto Mancini claimed United striker Rooney pressured referee into dismissing Kompany for a two-footed tackle on Nani but Ferguson says such appeals are now part of the game and that it was a reckless challenge.
Ferguson, speaking at the FIFA Ballon d'Or gala in Zurich, said: "I have no concerns about the behaviour in that respect because to my mind it was a reckless challenge and Nani is a very lucky boy because he didn't get a bad injury."
He added: "I have no complaints about Wayne, I don't think it was unacceptable what he did. I think it was a natural reaction to a bad challenge from an opponent.
"But I can understand where Roberto's coming from because that's what happens with players, they all appeal for penalties or players to be sent off, it's an unfortunate part of our game."
Rooney himself said on Twitter: "Funny how people think i got kompany sent off. Im not ref. i didn't give red card. But it was a clear red card. 2 footed tackle."
Ferguson also said he was relishing a fight to the end of the season with City for Premier League honours.
He added: "We have a big challenge from Manchester City but that's not a problem for Manchester United, we have faced these challenges for many years.
"It doesn't matter where it comes from, Chelsea, Arsenal, Liverpool or Tottenham, and Manchester City are a very good team.
"We know it's going to be a big, big fight towards the end of the season."