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 15 yards.
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 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.
After beginning the weekend in sixth, Bournemouth drop two places to eighth and 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.
A run of four draws in their past five games had stemmed some of the excitement generated during the early weeks of manager Unai Emery's reign.
But this impressive performance, against a side who began the day just four points behind the Gunners, will raise hopes among supporters that their side can sustain a top-four challenge this season.
With Alexandre Lacazette ruled out with a groin injury, Emery switched formation to a back three, with Aubameyang the lone striker.
The Gabon international responded by netting again and moving to the top of the Premier League scoring charts alongside Manchester City striker Sergio Aguero.
To further highlight his importance to the side, Aubameyang has now been directly involved in 23 goals in 26 league appearances since joining Arsenal from Borussia Dortmund in January.
The 29-year-old was ably supported on this occasion by Alex Iwobi and Henrikh Mkhitaryan, with 14 of the Gunners' 20 shots at goal coming from those three players.
The formation change also allowed Kolasinac to be a constant threat down the Arsenal left, with the Bosnia-Herzegovina international having a hand in both goals.