Brighton piled the misery on Arsenal with a hard-fought and deserved 2-1 win at the Emirates Stadium, where boos rung out at full-time in interim boss Freddie Ljungberg’s first home game in charge.
The visitors had never previously won away at Arsenal but they dominated the first half and withstood an Arsenal assault after the break before Neal Maupay headed home the decisive goal on 80 minutes.
Alexandre Lacazette had earlier cancelled out Adam Webster’s opener with a bizarre flicked header from a corner but Arsenal – who had a David Luiz strike rightly ruled out by VAR for offside at 1-1 – couldn’t find another way through, with Mat Ryan making a fine stop late on to deny substitute Gabriel Martinelli.
Arsenal, who have now gone nine games without a win in all competitions, remain down in 10th place in the Premier League and trail fourth-placed Chelsea by 10 points. Brighton, meanwhile, have pulled four points clear of the relegation zone and are up to 13th.
Aaron Connolly almost capitalised on a mix up between David Luiz and Bernd Leno inside 60 seconds and that set the tone for the first 45 minutes.
While Arsenal occasionally threatened through Pierre-Emerick Aubameyang down their right flank, the majority of the first half was played out in the hosts’ half, with Maupay fizzing a dangerous cross into the six-yard box which Connolly just failed to reach before the Frenchman forced Leno into a smart save.
Brighton – a real threat from set-pieces – won five corners in the first half and made their dominance count on 36 minutes when Webster reacted quickest to the loose ball in the box and slammed home.
Arsenal responded with Joe Willock testing Ryan with a good header before Lacazette rightly had his penalty appeals turned away when he went down under a challenge from Webster.
Arsenal brought record signing Nicolas Pepe on at half-time in place of Willock and their intensity was transformed after the re-start.
Within five minutes they were level.
Pepe probed down the right and won a corner and Lacazette’s flick-on from Mesut Ozil’s set-piece crept in at the back post while Sead Kolasinac and Davy Propper battled to turn it home.
There was a VAR check on Kolasinac’s challenge but after a nervy wait Arsenal’s equaliser was confirmed.
Brighton still had their chances, with Maupay just failing to connect from close range on 61 minutes but moments later David Luiz had a goal ruled out for offside by VAR, when he was judged to have gone too soon before sweeping home from a free-kick.
Arsenal were on top and seemed set to go on to win but Brighton impressively rode the storm and continued to cause their hosts problems.
Maupay – a thorn in Arsenal’s side all night – had a shot blocked by Sokratis on 79 minutes but then just moments later had the ball in the back of the net, pulling away from David Luiz to head home Aaron Mooy’s centre.
As the Arsenal home fans began to vent their anger, teenager Martinelli tested Ryan with a header and Pepe had a shot deflect wide but Brighton saw out the match to claim a deserved, valuable and historic three points.