Leeds manager Neil Warnock has criticised Chelsea's decision to file a complaint against referee Mark Clattenburg, claiming he is "on his side".
The European champions have accused the 37-year-old official of using "inappropriate language" to two of their players, Juan Mata and John Obi Mikel, during the stormy game at Stamford Bridge. The Metropolitan Police are now investigating the matter.
The accusations, understood to be based on alleged remarks that have been interpreted as racist, came at the end of a troubled day for Clattenburg, who sent off two Chelsea players and allowed United's winning goal to stand despite it being offside.
His most high-profile decision was to dismiss Fernando Torres for diving, with replays suggesting he was fouled by Jonny Evans. Warnock doubts whether a complaint would have been made had Chelsea won the game.
The former QPR boss told talkSPORT: "I'm disgusted at what has gone on. I am on Mark Clattenburg's side.
"We ask referees to deal with it and man-manage and that's what he does, Clattenburg. If Chelsea had won that game there would not have been one iota of a complaint.
"If it is proved wrong whatever Chelsea players alleged that Mark said, I hope they get done. Would it have happened if they won the game? I don't think it would have done."
Further incidents marred Sunday's game, with a steward reportedly suffering an injury following Javier Hernandez's winning goal for United.
Warnock's own club, Leeds, have been no strangers to trouble of late either, with one of their fans last week jailed for attacking Sheffield Wednesday goalkeeper Chris Kirkland.
Leeds supporters were also branded "vile animals" by Wednesday boss Dave Jones for some of the chants they were singing about child abuse charges against him which were dropped, and Warnock wants the state of football to be changed.
"The chanting has come back, in the Sheffield Wednesday game they were chanting about everybody. Everybody got stick, above the normal type you get," he said. "Chants of Istanbul (where two Leeds fans were murdered) and everyone else. I don't see where it's come from but it is getting a bigger situation at grounds.
"A lot of these are grown men in suits with kids. I think it's getting worse and I don't know what the answer is. It's got to come from within the club or the group of fans.
"When you see the hatred in some of the supporters' faces, you can't ask a steward to go and climb in the middle of them and bring somebody out, they would get killed."