The Dutchman, 64, said speculation he offered to resign after the 1-0 loss to Southampton was "awful and horrible".

In a swipe at the media, he claimed journalists had "sacked" him three times already this season, and would do so again if United lose at Derby.

"Maybe then you have written the truth because sometimes it happens," he said.

United are 10 points behind Premier League leaders Leicester, five points adrift of Tottenham in fourth place and out of the Champions League.

Speaking before Friday's fourth-round match with the side fifth in the Championship, Van Gaal said questions about his future were being asked in a "disrespectful way".

You make your stories and people believe it," he said at a news conference. "I am concerned they are believing it. You can write what you do.

"It is the third time I am sacked and I am still sitting here. Now I cannot lose any more - then for the fourth time I have been sacked."

Van Gaal praised the "fantastic" support of executive vice-chairman Ed Woodward and said an FA Cup win could be his saviour - as it proved for former United boss Sir Alex Ferguson in January 1990.

Ferguson was three years into the job at Old Trafford and United wereplummeting towards the old First Division relegation zone when they faced Nottingham Forest in the FA Cup third round.

It was believed that a defeat would see Ferguson sacked. They won 1-0 and Ferguson went on to become English football's most successful manager.

Asked whether the FA Cup could become his saviour, Van Gaal said: "Of course."