Manchester United boss Sir Alex Ferguson has accused referee Howard Webb of favouring Arsenal in the 2-2 draw at the Emirates.
Ferguson complained of a hostile crowd at Arsenal
The Gunners twice came from behind to salvage a draw at home on Saturday.
"I think Howard Webb has a great chance to be the top referee but today was a big game for him and, at times, he favoured Arsenal," Ferguson told MUTV.
"Their second goal came from him not giving a free-kick for a foul on Louis Saha. It should've been a foul for us."
However, Ferguson stated it was hard for referees not to be influenced by hostile home crowds.
I am pleased that in two big games we had to run after the score and we did that both times
Arsenal manager Arsene Wenger
"It is very difficult for the referee," he added. "On our bench, we were getting terrible abuse from people two or three feet away from us.
"There is a lack of security. It is absolutely disgraceful the abuse you and your staff take. All sorts of things are being shouted and screamed at you and there is an absolute danger here."
However, a spokesperson for the Gunners said: "Stadium security is of the highest importance and we feel there is ample stewarding around the dugout area.
"However, the club does recognise that some exchanges which take place can be of an aggressive nature, and there was an incident this afternoon where one supporter was ejected.
"There is also CCTV which monitors the area which our stadium management crew review in detail after games, and if necessary the club will take further action."
Ferguson thought his side had done enough to win the match when Cristiano Ronaldo put them 2-1 up with eight minutes left.
But William Gallas, whose own goal had given United a first-half lead before a Cesc Fabregas goal, volleyed an injury-time equaliser for the Gunners.
"Our character was tested twice," said Arsenal manager Arsene Wenger. "Just before half-time and with eight minutes to go.
"Overall though, I believe it was a fair result. We played with the handbrake on in the first half, though, and we lacked our usual flowing game."
It was the second time in successive league matches that Arsenal had drawn against top opposition, having drawn 1-1 at Liverpool last Sunday.
And Wenger was frustrated not to have taken at least four points from the two games.
"That is a disappointment," he added. "But on the other hand I am pleased that in two big games we had to run after the score and we did that both times.
"We are still in charge of the title race because we are top with a game in hand."