Arsenal lost their hold on the Premier League summit after a 3-0 defeat by Brighton, who marked the club’s 125th anniversary with a commanding performance. Pascal Gross and the 19-year-old Charalampos Kostoulas struck in the first half, and new signing Chema Andrés sealed the win with a header 12 minutes into the second period from a Gross corner.

Brighton’s victory highlighted the depth of a side already the division’s leading scorers, 16 in five games, despite missing much of their first-choice forward line through injury and the summer sale of last season’s top scorer, Danny Welbeck, to Chelsea. Georginio Rutter only returned as a late substitute, while Brighton’s press, led by Kostoulas, repeatedly forced Arsenal into mistakes.

Arsenal’s goalkeeper David Raya was forced into a smart stop to turn a deflected Kostoulas effort around the post and was also guilty of giving the ball away to Yasin Ayari in a dangerous area. A misplaced pass by Bruno Guimarães presented Gross with the chance to score, and Gross picked his spot off the inside of the post. Ayari drew a save and later hit the side-netting before Kostoulas thumped in a long-range finish from about 25 yards.

Jurriën Timber made his first start since March but looked short of sharpness, Bruno Guimarães failed to make an impact on his first Premier League start for the club, and Arsenal missed the drive they had from Myles Lewis-Skelly, who was absent after a recall to the England squad. Bukayo Saka spurned a good opportunity after being set up by Martin Ødegaard, and Mikel Arteta turned to 16-year-old Max Dowman on the bench, who had scored twice for the club in midweek.

Brighton celebrated in special deep-blue commemorative shirts inspired by their 1901 season, a kit that had attracted controversy after being listed for sale at £150 in a package including a letter of authenticity from owner Tony Bloom and a keyring. Supporters sang, "Are you Tottenham in disguise?" as the home side completed a comprehensive victory.

Mikel Arteta conceded the visitors’ superiority, saying, "They deserved to win." Arsenal face a three-week international break with questions to answer after being knocked off the top of the table on goal difference, while Brighton sit in third, two points behind Arsenal in the early-season standings.