In Pictures: Manchester United 2 Arsenal 1
Arsene Wenger was sent off as Arsenal were denied a last-gasp equaliser in a thrilling encounter with Manchester United.
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Wenger must have already been raging at the injustice of it all as an outstanding performance from his team threatened to go unrewarded thanks to Wayne Rooney's controversial second-half penalty and an Abou Diaby own goal.
But when what would have been an equaliser with virtually the last kick for Robin van Persie was ruled out for offside against William Gallas, it was too much for Wenger, who lashed out in frustration and was sent to the stands by referee Mike Dean.
After a laughable delay as Wenger got as near to the action as he could by clambering onto the top of the dug-out, the Frenchman made his way to the tunnel, lingering long enough to witness the last dregs of an epic.
After ranting yesterday about the "witch-hunt" that accompanied Arsenal's penalty against Celtic in midweek, the bitter irony of his side being turned over in very similar fashion could not have been lost on the Frenchman.
The Gunners were in front and on top when Rooney went down under Manuel Almunia's challenge just before the hour mark.
There was at least some contact this time but it was limited enough to leave Wenger gnashing his teeth, especially as Andrey Arshavin had been denied a stone-wall spot-kick earlier.
The outcome was the same as Eduardo achieved earlier in the week. Rooney sent Almunia the wrong way, ensuring the only blot on Diaby's fine performance turned out to be the own goal that sealed a win that wrecked Arsenal's 100% start to the season.
It had all looked so unlikely at half-time, as Arshavin threatened to run riot.
The Russian might have scored earlier than he did too when Ben Foster flapped at a Van Persie corner.
The former Zenit St Petersburg man made a conscious effort to place a shot towards the top corner. Foster was not the only anxious face to watch it drift narrowly wide.
Given what happened immediately afterwards, Foster would probably have preferred Dean to have got his decision right when Darren Fletcher slid into Arshavin and cut him down inside the box.
There could have been few clearer penalty claims and Dean was standing near enough to make the perfect decision. Inexplicably, he chose to say no.
Instead, Arsenal maintained their offensive. The impressive Denilson slid a pass through to Arshavin, who had found space between United's defence and midfield which Ferguson's team selection was supposed to prevent.
Quickly Arshavin turned and let fly with a rasper of a drive.
There was plenty of pace on the shot but England goalkeepers should really be doing better than pushing it into the roof of the net, as Foster did.
Nemanja Vidic came close to levelling straight away for the hosts but, as they trooped into the tunnel for a dismal half-time debrief, the best they could actually reflect on was a Rooney free-kick that curled narrowly wide.
Strangely given how one-sided the opening half had been, Ferguson did not try to change things during the interval. And his team were almost out of the game before he had retaken his seat.
Arshavin sped past John O'Shea as though the Irishman was not there to reach the by-line and picked out Van Persie with a teasing low cross that looked certain to be number two until Foster stuck out a leg to make a magnificent save.
At that point, there seemed to be only one winner. How wrong those doubters were as Ferguson's team surged back, Ryan Giggs the architect behind the comeback just as Arshavin had sparked Arsenal earlier.
The difference was Dean said yes when United claimed their penalty as Rooney went crashing to the ground after Giggs had supplied the pass that sent him through one-on-on with Almunia.
Questions were asked when Rooney did not take the one Michael Carrick missed at Burnley. There was no need this time as Rooney went straight for the ball, put it on the spot and promptly sent Almunia the wrong way.
Any pretence at defence was now swept away amid the fervour of an occasion that threatened to become a classic.
When Diaby was hacked at by Rooney and Wes Brown, both men were booked and Van Persie was offered the chance to curl a free-kick at Foster's goal which thudded against the crossbar.
A minute later, from a very similar position, United got their second.
In truth, Giggs' free-kick would not have threatened Almunia if Diaby had not stuck his head on it and deflected it straight into the corner of his own goal.
In this, of all weeks, Emmanuel Eboue really should not have been going down under a non-existent challenge from Patrice Evra that rightly got him booked.
It was just the start of more controversy.