In a statement issued on the official club site the Uruguayan striker said: "I have spoken with the Manager since the game at Old Trafford and I realise I got things wrong.
"I've not only let him down, but also the Club and what it stands for and I'm sorry. I made a mistake and I regret what happened.
"I should have shaken Patrice Evra's hand before the game and I want to apologise for my actions.
"I would like to put this whole issue behind me and concentrate on playing football."