Zat Knight produced a stoppage-time equaliser as Arsenal threw away a two-goal lead and missed the chance to return to the top four in a 2-2 draw with Aston Villa.
The five-million-pound signing from Fulham was given a rare starting place by Villa manager Martin O'Neill in place of the injured Martin Laursen, and the defender came up with a rare goal. Abu Diaby and Denilson had given Arsene Wenger's side the chance to avenge their 2-0 defeat by Villa at the Emirates several weeks ago.
Arsenal maintained their excellent record at Villa Park, extending their unbeaten run to ten games, but this will feel like they have thrown two points away as they allowed Villa to retain their place in the top four and stay three points in front of the Londoners.
Arsenal have not had much in the way of good fortune of late, especially with the loss of captain and play-maker Cesc Fabregas, who will be out until April with his partially ruptured medial knee ligament injury, but they had more than their fair share in the opening 45 minutes at Villa Park.
From the moment Steve Sidwell's header struck the post with Manuel Almunia beaten, Arsenal lived a charmed life against the side who look most likely to mount a serious challenge to their place in the top four this season.
Luke Young saw another effort tipped over the bar by the Spanish goalkeeper, who was in imperious form to keep Martin O'Neill's side at bay. One full length save, to deny Gabriel Agbonlahor was exceptional and was followed by great commitment from William Gallas who had to dive full length to stop Sidwell's follow-up shot from finding the target.
James Milner, the England under-21 international was also denied, by Almunia at the near post as he slid in to meet Young's deep cross and even defender Curtis Davies got in the act, hooking a shot over the Arsenal keeper and on to the crossbar. Villa were clearly rattled by the manner in which Wenger dismissed their chance of winning the Premier League title this season.
And they could have been forgiven for thinking it was not to be their day when, having managed to avoid the post, bar or Almunia, they saw an overhead kick on the goal-line from Arsenal defender Bacary Sagna turn away an on-target shot from Agbonlahor.
So much pressure and nothing to show for it was bad enough, but to add insult to injury Arsenal stole the lead five minutes before the interval. Denilson's attempted one-two with Emmanuel Eboue, hit the shins of Nigel Reo-Coker and the Brazilian accepted the loose ball, before shooting beyond Brad Freidel.
On that basis, what happened immediately after the break was a dreadful blow to Villa as they fell further behind within three minutes to a contender for goal of the season.
Abu Diaby's brilliance was worth the entrance fee alone. He started the move deep in his own half and ran 70-yards to accept Eboue's invitation to shoot beyond Freidel.
But Villa are resilent as well as entertaining these days and they pulled a goal back when Gallas pulled down Agbonlahor in the area for Gareth Barry to score in the 65th minute from the penalty spot - before the late, late show by Knight ruined Wenger's day.