An own goal from Pierre Emerick Aubameyang handed Burnley their first win at the Emirates Stadium in 46 years and Arsenal’s fourth straight league games loss.
Arsenal’s bad evening began when Granit Xhaka was sent off after he violently grabbed Ashley Westwood by the throat early in the second half.
The 10-man hosts tried to rally in the closing stages, with Bukayo Saka seeing a goalbound effort headed over the bar by James Tarkowski, but Burnley held firm to claim only their second Premier League win of the season.
Before Xhaka’s red card, the Gunners appeared to be gaining the upper-hand after the interval at the Emirates Stadium, with Nick Pope making a string of saves following a blunt first-half display from the hosts.
The home defeat to struggling Burnley means it is the first time since 1959 that Arsenal have lost four consecutive home games in the league, with just one win in the last eight games.
Next, Arsenal are back at the Emirates Stadium to face Southampton on Wednesday while Burnley travel to Villa Park to face Aston Villa on Thursday.