Bobby Zamora scored in the final minute of injury time to help Fulham come from behind to beat 10-man Arsenal.
The visitors dominated the first 45 minutes, but only had Laurent Koscielny's header to show for it.
Fulham's Philippe Senderos and Clint Dempsey went close in a one-sided second half before Johan Djourou was sent off for a second yellow card.
Steve Sidwell headed an equaliser in the 85th minute and Zamora volleyed home to seal a dramatic victory.
It was an incredible turnaround in fortunes for Martin Jol's men, who should have been out of the contest by half-time.
With Mikel Arteta and Aaron Ramsey pulling the strings in midfield, they were left chasing shadows for much of the first half.
But while it was a masterclass in possession from Arsenal, some of their finishing left a lot to be desired.
The Gunners were wasteful in attack, with Theo Walcott and Gervinho particularly frustrating in their inability to finish off some free-flowing moves.
Gervinho was, however, unlucky not to win a penalty when he was tripped by Senderos after good work from Robin van Persie.
With the Gunners in total command, it was no surprise when they took the lead, as Koscielny headed home Ramsey's deflected cross from close range.
The defender was left unmarked in the area, a worrying trait that continued to blight the cavalier Cottagers throughout the first half.
They were reliant on poor Arsenal finishing and some exceptional goalkeeping from David Stockdale to remain in the game.
The pick of the keeper's saves came when he denied Ramsey and Alex Song in the same attack - the second of the close-range stops underlining why England manager Fabio Capello thinks so highly of the 26-year-old.
Fulham did enjoy one bright moment towards the end of the half when Bryan Ruiz shot wide after a mazy run at the heart of the visitors' defence.
The home side improved after the break with former Arsenal trainee Sidwell twice going close, first with a header and then with a long-range shot that just cleared the bar.
Jol's men were showing much more urgency and ambition, causing Arsenal to retreat, and both Senderos and Clint Dempsey headed glorious chances wide.
And Fulham were left cursing their luck once again when Ruiz saw his shot saved by Wojciech Szczesny.
However, they were given hope when the Gunners were reduced to 10 men after Djourou was shown a second yellow card for a foul on Zamora.
The improbable became possible when Sidwell headed home a corner that Arsenal failed to clear, and the Fulham supporters were soon delirious when Zamora stabbed home Stephen Kelly's cross.
It was no more than they deserved for a stirring second-half fightback that combined class and character.
Arsenal supporters were daring to dream of a crack at the Premier League title at half-time. By full-time, they will be left wondering whether a top-four finish is achievable.