Manchester City are angered that while Sir Alex Ferguson has escaped punishment for his confrontation with match officials on Boxing Day, their own manager, Roberto Mancini, has been censured for making a joke about referee Kevin Friend.
The Football Association has written to City asking them to explain his comments following their 1-0 defeat at Sunderland that Friend had "eaten too much over Christmas". Manchester City will argue that Mancini was trying to be funny in a press conference in a language that is not his own. He was not, unlike Ferguson, confronting a referee in the full glare of the pitch.
The Queen's Park Rangers manager, Harry Redknapp, has also been asked to explain his observation that the linesman at Loftus Road on Boxing Day "should have gone to Specsavers".
However, the FA takes a dim view of anyone attempting to criticise the physical fitness of a match official. When Ferguson attacked Alan Wiley for being not fit enough to referee a 2-2 draw with Sunderland at Old Trafford in October 2009, he was fined and given a two-match touchline ban. Ferguson apologised.
The Manchester United manager was in absolutely no mood yesterday to apologise to Alan Pardew, who suggested he should have been sent to the stands for his confrontation with referee Mike Dean and his officials.
Ferguson labelled the Newcastle manager a bully and a hypocrite, adding that Pardew was one of the worst abusers of referees in the country who was in charge of "a wee club in the North-east".
Ferguson argued he had been "demonstrative" rather than "ranting" when, before the second half began, he argued with Dean, the linesman, Jake Collin, and the fourth official, Neil Swarbrick, over the decision to allow Newcastle's controversial second goal at Old Trafford.
Dean did not mention the incident in his report, which Pardew said was something the referee would regret. Dean, he argued, "should have done something about it".
Ferguson was withering in his assessment of Pardew, who in August was given a two-match ban for pushing the linesman Peter Kirkup after he had ruled the ball had gone out of play.
"The problem for me and for Manchester United is that the profile of the club is huge and Alan Pardew has come out and criticised me," Ferguson said. "Alan Pardew is the worst at haranguing referees.
"His whole staff do it every game. They were at it the whole time on Wednesday. He shoved a linesman and made a joke out of it – and he has the cheek to criticise me. It is unbelievable. He forgets the help I gave him, by the way.
"The press have had a field day. The only person they haven't talked to about this is Barack Obama and that's only because he's too busy. That is unfortunate because I am the manager of Manchester United, the most famous club in the world. I am not at Newcastle, a wee club in the North-east."
Ferguson said his remarks to Dean that Papiss Cissé had been interfering with play when Jonny Evans put through his own goal in United's breathless 4-3 win had been measured. "I called him over and said there was body contact [between Evans and Cissé] and the rules say, if a forward is interfering with a defender, he is offside.
"The interpretation from Mike Dean was that he was not interfering and so that is a moot point. He is an experienced referee, mature, and there was no ranting or raving from me. I was demonstrative but then I am always demonstrative. I am an emotional guy. That does not make it abuse of the referee. Some managers shove linesmen on the pitch and make a joke of it. I am not making a joke of it. This was a serious incident."
It may have been another thrilling United comeback but Ferguson is desperate for the drama to stop. Of United's 27 games in all competitions, seven have finished 3-2; there have been two 4-3s, one 5-4 and one 4-2. "Of course it matters," he said when reminded that United had still won nine of those 11. "If we are scoring four goals at home, there should be one against us at the most."
Red mist: When Ferguson hits back
* "Wenger was criticising my players, calling them cheats. He ran at me with his hands raised. To not apologise for the behaviour of players is unthinkable. It's a disgrace, but I don't expect Wenger to ever apologise – he's that type of person." January 2005, on Arsène Wenger
* "[Jose] Mourinho seems to be on some sort of personal crusade. I am surprised no action has been taken. It's calculated." April 2007, on the then Chelsea manager Mourinho
* "He was an angry man. He must have been disturbed for some reason. You have to cut through the venom and, hopefully, he'll reflect and understand what he said was absolutely ridiculous." January 2009, on the former Liverpool manager Rafael Benitez
* "[Roberto] Mancini was badgering the ref and the fourth official all game. He was complaining about refs all week, but can't complain about this one." April 2012, following United's 1-0 loss at Manchester City