United supporters should lay off 'Le Prof'...
United travel to the Emirates on Sunday for an eagerly-awaited Premier League clash but Ferguson does not want passion to spill over into abuse.
"I know there has been some terrible abuse from our fans towards Arsene Wenger," the Scot told reporters at his Friday press conference.
"But a line has to be drawn. They must know that themselves."It is unavoidable that managers do get abused.
"I get it myself. Most managers do.
"Sometimes I can't hear these chants, or make them out but it has to be controlled.
"There is none better than our support, as it showed on Wednesday [against Manchester City]. I was really proud of them.
"But they have a team to support. They don't need to worry about anyone else. They should be proud of the players."
Meanwhile, the Scot is relishing the chance to test himself against the Gunners again in a game that could go a long way to determining the ultimate destination of this season's Premier League title.
"This is the biggest game of the season for us," the United boss affirmed.
"Arsenal have gone on a consistent run and it's amazing how this league has changed.
"The team that is most consitent will win the league now and Arsenal's current form has been very good and I'm looking forward to it.
"At the monent the league is looking like a three-horse race but there have been so many changes and different results that even the top sides cannot be 100 per cent certain.
"Of course Chelsea have the advantage of the game in hand, and if they win that then they go four points ahead of us.
"That is the catch-up part we are in and that means Sunday has a great relevance to us both because we both have a genuine chance to win the league."