Olivier Giroud's stoppage-time header earned Arsenal an unlikely 3-3 draw at Bournemouth after they had looked down and out when trailing 3-0 after 70 minutes of a rivetting Premier League clash on the south coast on Tuesday.
Fourth-placed Arsenal's title challenge looked set for a massive dent when Ryan Fraser's breakaway goal put Bournemouth three up just before the hour mark after Charlie Daniels and Callum Wilson scored before the break.
Alexis Sanchez's diving header threw Arsene Wenger's side a lifeline with 20 minutes remaining though and when Lucas Perez volleyed in shortly afterwards the comeback looked on.
Dan Gosling went close to a fourth for a panicky Bournemouth and the home jitters increased when skipper Simon Francis was red-carded for a clumsy tackle on Aaron Ramsey after 82 minutes.
Bournemouth's creaking defence crumbled in the second of six minutes of stoppage time when Giroud stretched his neck muscles and to meet Granit Xhaka's cross and glance a header just inside Bournemouth keeper Artur Boruc's post.
Arsenal sensed a remarkable victory but time ran out and they remained in fourth spot with 41 points from 20 games, eight behind leaders Chelsea who play at Tottenham on Wednesday.
Despite their remarkable revival, there was a sense of deflation for Arsenal's players as they trudged off.
"I'm pleased to help the team by scoring the equaliser but I'm still disappointed," France striker Giroud, who scored a wonderful "scorpion" goal in Arsenal's win over Crystal Palace on Sunday, told Sky Sports.
"It's nice to come back but the way we played at the end, that made me think we should have done better. At least we came back, showed great mental strength and I will take it."
Had Arsenal started the game the way they finished it the outcome would have been different and Wenger's side would have turned up the heat on Chelsea by moving third.
They were casual though and were punished by Eddie Howe's tenacious Bournemouth team.
The marking was non-existent in the 16th minute when Junior Stanislas picked out Daniels with a raking pass and he stepped inside Hector Bellerin's half-hearted tackle to beat Petr Cech.
Worse was to follow four minutes later when Bournemouth broke and Fraser burst into the area before being levered to the ground by the back-tracking Granit Xhaka for a clear penalty.
Wilson's spot kick was not cleanly struck and straight down the middle but Cech had dived the other way.
There was more urgency about Arsenal in the second half but they found themselves 3-0 down when Fraser got away with a shove on Bellerin before cutting in to shoot through Cech's legs.
Bournemouth's fans chanted "we want four" but half an hour later they were desperately checking their watches as Arsenal almost snatched victory from the jaws of defeat.
"The key moment was that first goal for them, the game changed after that," Howe, who took over eight years ago when Bournemouth were in the fourth tier, said.
"It should have been safe at 3-0. But I think we were harshly treated with the red card."
Reporting by Martyn Herman; Editing by Toby Davis