Arsenal endured a chastening afternoon at the Amex Stadium as Brighton dismantled Mikel Arteta's side 3-0, exposing alarming defensive fragility from the opening whistle. The visitors never settled into any rhythm, overwhelmed by the home side's pressing and energy throughout.
Pascal Gross and Charalampos Kostoulas punished sloppy Arsenal defending with long-range strikes to put Brighton in control, before Chema Andres headed home a third from a corner after the interval to complete the misery.
Goalkeeper David Raya struggled with his distribution early on and could do little to prevent either of Brighton's opening two goals from distance, though he did produce a smart late save to deny O'Riley. In front of him, the defence was in disarray. Jurrien Timber, making his first start since mid-March, looked understandably short of sharpness and was caught badly out of position for Andres' goal. Ezri Konsa also struggled on the ball and was repeatedly bullied when Brighton attackers ran at him directly.
Gabriel had arguably his worst outing in an Arsenal shirt, standing off Brighton's forwards for both early goals and compounding matters with what was described as an embarrassing dive, going down under no contact whatsoever. Riccardo Calafiori shared blame for failing to close down Gross before his strike and was similarly slow to track back as Brighton broke forward with ease, though he did whip in one promising cross late in the match.
Declan Rice stood out as one of the few Arsenal players to offer any resistance, battling almost single-handedly in midfield and driving forward on occasion, but he received scant support from his teammates. Bruno Guimaraes, by contrast, was overwhelmed by Brighton's tempo, careless in possession and sluggish defensively, to the extent that some felt he should have been substituted at half-time.
In attack, Bukayo Saka was among the better performers, showing willingness to run at his marker and setting up a chance for Christos Tzolis, though his end product ultimately fell short. Martin Odegaard struggled to impose himself and vanished when Arsenal most needed composure, while Tzolis continued his poor run of away form, missing a good opportunity created by Saka before fading out of the game entirely in the second half.
Kai Havertz endured a miserable display up front, unable to hold the ball up and making a costly error when dropping deep, conceding the corner that led directly to Brighton's third goal. He did have a clear sight of goal to pull one back but fired straight at the goalkeeper.
Arteta's changes did little to alter the course of the match. Martin Zubimendi and Mikel Merino, introduced together, failed to lift the tempo, while Eberechi Eze was jeered by the home crowd upon entering the fray and barely featured afterwards. Viktor Gyokeres offered a slight improvement after replacing Odegaard, linking play well and setting up Havertz's chance, while youngster Max Dowman came on late for Saka.
The heavy defeat raises serious questions for Arteta about his side's mentality and defensive organisation as they head into a challenging run of fixtures, with several senior players producing performances well below their usual standards.
Based on reporting from Standard Sport.