SIR Alex Ferguson blasted the match officials after Manchester United's 2-1 defeat by Chelsea, which gave Carlo Ancelotti's side the advantage in the Barclays Premier League title race.
Joe Cole put the visitors ahead but it was Didier Drogba's goal 11 minutes from time that left Ferguson fuming, with replays showing the striker was clearly offside.
The United boss told Sky Sports 1: "What I can't understand is the linesman's directly in front of it. He has no-one near him and he gets it wrong.
"A game of that magnitude, you really need quality officials and we didn't get them today. It was a poor, poor performance."
Referee Mike Dean has been in the spotlight this week after Blackburn's Martin Olsson admitted he deliberately went down in the area at Burnley because of Dean's reputation for giving penalties.
United had two penalty appeals turned down today while Chelsea also looked to have a good shout when Gary Neville barged Nicolas Anelka.
Asked whether Dean had been affected by the comments, Ferguson added: "I don't know about that but when I saw Mike Dean I did worry, I must admit."
Chelsea now lead United by two points with five games to go, and Ferguson put the pressure on his rivals by making them firm favourites.
"Five games left, they're two points ahead and four goals better than us - they're in the driving seat," he continued.
"Chelsea are favourites now, there's no question. I'm certain we'll respond but we could win the next five games and not win it."