Wenger's worry shows after the Old Trafford clash
The latest explosive episode in the long-running battle between Manchester United and Arsenal is predictably dominating the back pages and airwaves.
But what did the angry scenes at Old Trafford really mean for those involved - and what does it mean for the championship race?
Whenever things get nasty between United and Arsenal, Sir Alex Ferguson comes out smiling.
One of Ferguson's favourite motivational tactics is to create the impression in his players' minds that it is them against the world, and that the world is out to get them.
It is one of the reasons why he consistently manages to get a collection of millionaires to fight from kick-off to final whistle like fresh-faced trialists battling for their football future.
Arsene Wenger, by contrast, comes away from scraps like Sunday's wearing the annoyed look of a man who has spent the afternoon scratching away at a persistent itch.
Wenger is a calm, logical man who is used to thinking his way around problems, a man for whom losing your temper is a sign of weakness. But United, and Ferguson in particular, get under Wenger's skin, and that irritates him.
Ferguson is happy to be seen as a ranter. Wenger is not, which is why he will have woken up on Monday morning the less satisfied of the two, despite a battling point at the home of his greatest rivals.
None of the players directly involved in Sunday's handbags have come out of the game with any credit.
The kick that kicked it all off
Patrick Vieira now has the unwanted honour of having been sent off more times in the Premiership than any other player.
His leg-waving at Ruud van Nistelrooy may not have been the ugliest incident in this or any other season, but under the laws of the game it deserved a second yellow card.
And Vieira, as captain and chief offender, will now be the centre of the attention as Arsenal's woeful disciplinary record comes under renewed focus.
Neither will Van Nistelrooy escape untarnished. Wenger's acerbic comment that the Dutchman, "looks a nice boy on the pitch but doesn't always go in for nice behaviour", is the sort of verbal barb that can stick in the minds of referees and subconsciously encourage them to treat a player with increased suspicion.
Martin Keown won't care in the slightest what anyone thinks of him, but his reaction to Van Nistelrooy's penalty miss was hardly becoming of an England international with 20 years experience of professional football.
The final explosive minutes at Old Trafford masked a more significant truth - that neither Manchester United nor Arsenal played like Premiership champions elect.
In a game devoid of goalmouth chances, United were sorely lacking the guile of the injured Paul Scholes and departed David Beckham.
For all his step-overs and feints, Cristiano Ronaldo produced little of real significance. Quinton Fortune and Phil Neville worked hard, but inspiration was in desperately short supply.
Arsenal may have shored up the defence which leaked so badly against Inter Milan, but they failed to create a single chance of note.
Meanwhile, down in west London, Claudio Ranieri must have been rubbing his hands with glee. While the two great rivals of the last decade absorbed themselves in a self-destructive bore-draw, Chelsea were relaxing after the easiest of 5-0 wins.
True, that thrashing was only of Premiership whipping-boys Wolves. But Chelsea's expensive stars have gelled far quicker than anyone dared think.
The past weekend gave the clearest indications yet that the title race this season is no longer a two-horse affair.