Arsenal fought back from three goals down to claim a 3-3 draw with West Ham in a thrilling London derby on Sunday.
David Moyes side had carved out a three-goal lead with just over half an hour gone as Jesse Lingard, Jarrod Bowen and Tomas Soucek capped off a blistering start.
But a Soucek own goal late in the first half swung momentum toward the Gunners, who set up a thrilling finish by forcing Craig Dawson to put through his own net with 30 minutes remaining.
And Alexandre Lacazette completed the comeback late on as he headed home from close range to steal a share of the points.
An exhausting encounter at London Stadium and it ends with the points being shared!
3-3 (FT)
— Arsenal (@Arsenal)
Perhaps feeling the physical toll of their midweek Europa League commitments, Arsenal made a slow start to proceedings.
And, after spending the opening 10 minutes penned in their own half, they deservedly fell behind when Lingard controlled Michail Antonio s cutback at the edge of the area and thrashed a beautiful effort into the top corner.
Mikel Arteta might have hoped that setback would wake his team up, but they were two down just two minutes later, Lingard s quick free-kick releasing Bowen to squeeze a low effort past Bernd Leno s weak save attempt.
Soucek made it three with just over half an hour gone, poking Antonio s goalbound header home as West Ham capitalised on more loose passing and poor defending from Arsenal.
To their credit, the visitors responded well, with Lacazette diverting in a powerful effort from just inside the box with the help of a deflection off Soucek that was only apparent on replays.
Bukayo Saka twice went close to reducing the deficit before the break, seeing a one-on-one well saved by Lukasz Fabianski and another shot dribble just wide of the post, but the Gunners could have few complaints over the half-time scoreline given their start.
Encouraged by a strong finish to the first half, Arsenal started the second well, and went close to a second as a Lacazette lob was acrobatically cleared off the line by Issa Diop.
But they got their reward just past the hour mark when Dawson inadvertently turned home a low and powerful Calum Chambers cross from the right-hand side.
And, after Antonio missed a chance to seal the points by hitting the post from close range, Lacazette brought Arteta s men level as he headed in a teasing right-wing cross from Nicolas Pepe.
Pepe and Declan Rice traded efforts at goal in an end-to-end finish at the London Stadium, but neither side were able to steal the win at the end of a thrilling contest.
What does it mean?
Defeat to Manchester United last time out cast doubt upon West Ham s top-four credentials, and they looked set to provide the perfect response here after racing into the lead.
However, rather than drawing level with fourth-place Chelsea, West Ham now sit two points adrift after a result that could serve to damage confidence in their Champions League chase.
As for Arsenal, a point is not enough to get their league campaign on track, leaving the Europa League as their most probable route back to European competition next term.
Leno lets Gunners down
It perhaps seems harsh to single out one goalkeeper for criticism in a game that saw both teams score three goals, but Bernd Leno must take some blame for how this one panned out for his side.
Had the German not allowed a weak Bowen effort to squirm past him moments after West Ham had gone 1-0 up, Arsenal could have been left reflecting on a fine comeback win here.
Instead, he ended the afternoon having faced five shots on target and having saved just two.
Antonio leads West Ham forward
A slight nick off Soucek s foot may have denied him a certain goal from a header, but Antonio was clearly West Ham s main man in attack here.
As well as getting two assists, the forward took more shots than any other player on the pitch (5), and laid on five key passes.
Key Opta Facts:
West Ham failed to win after being three goals ahead in a Premier League game for the first time since September 1998 (3-4 v Wimbledon). Arsenal, meanwhile, avoided defeat in a Premier League game they trailed by 3+ goals in for only the second time – previously doing so v Bournemouth in January 2017 (3-3).
This was the third time in the Premier League season that a team has led by 3+ goals and failed to win (also West Brom 3-3 Chelsea and Spurs 3-3 West Ham) – the most instances in a single Premier League campaign since 2010-11 (also three).
West Ham have only won one of their last 11 games against Arsenal in the Premier League (D3 L7), failing to win any of their four meetings in the last two league campaigns (D1 L3).
Jesse Lingard scored his fifth goal against Arsenal in all competitions the most he has netted against any opponent in his professional career.
What s next?
Arsenal s next fixture sees them host Premier League champions Liverpool at the Emirates Stadium following the international break.
West Ham, meanwhile, will head to Wolves that same weekend as they look to get their push for a top-four finish back on track.