Manchester United manager Sir Alex Ferguson has vowed to fight improper conduct charges following his criticism of referee Martin Atkinson.

Ferguson appeared to question Atkinson’s impartiality following United’s 2-1 loss at Chelsea on Tuesday, which saw the Red Devils manager hit out at Atkinson’s failure to dismiss Blues defender David Luiz.

The United manager has been charged with improper conduct by the English FA and faces a lengthy touchline ban if they are upheld.

“Sir Alex has responded to the FA today to deny the charge of improper conduct. He has requested a personal hearing,” a spokesman for United said.

In a scathing post-match tirade broadcast on Manchester United’s official television channel, Ferguson gave a damning verdict on Atkinson’s display.

“You want a fair ref. I don’t know how he got this game. I must say, when I saw who it was, I did fear that,” Ferguson told MUTV.

“It’s three years in a row that decisions have changed the game here. It was incredible.

“You are talking about what changed the game in the second half. These are decisions that change the game and he is going to be refereeing every week!

“I’m proud of my players. They endured a lot of bad decisions against them and they have done their best.”