Arsenal moved to within one point of the Premier League top four and extended their unbeaten run in all competitions to 17 games with victory at Bournemouth.
The Gunners took the lead thanks to a spectacular own goal from Cherries midfielder Jefferson Lerma, who volleyed Sead Kolasinac’s cross past Asmir Begovic from far out.
Joshua King, making his comeback after four games out with an ankle injury, finished off a swift counter-attacking move to bring the hosts level just seconds before half-time.
But Pierre-Emerick Aubameyang scored what proved to be the winner after the break when he converted Kolasinac’s cross for his eighth Premier League goal of the season and Arsenal’s 1,800 league goal.
Despite the defeat, Bournemouth stay eighth on the table but have now lost their past three league matches.
The Cherries were aggrieved early on when David Brooks had a goal ruled out for offside, with replays suggesting he was marginally behind Shkodran Mustafi when the ball was played.
But that proved the catalyst for a confident display from Arsenal, who secured their fourth Premier League away win of the campaign – equalling their tally for the whole of last season.