After finishing in eighth place in the Europa League – four places and 10 points behind fourth-placed Chelsea – Mikel Arteta’s side were in danger of missing out on European football next season, but Aubameyang had other ideas.
Christian Pulisic, who hobbled off injured in the second half, had put Frank Lampard’s men in front after five minutes but Aubameyang levelled up after being brought down by Cesar Azpilicueta.
After slotting home from the spot midway through the first half, a moment of magic from the Gabon international in the second period put the Gunners 2-1 up, with Matteo Kovacic sent off five minutes later for a, perhaps harsh, second yellow card offence.
Arsenal are the most successful side in the competition’s history and they were good value for their 14th FA Cup success.
It was, however, another sign of how much they rely on their talisman, whose contract has less than a year to run.