Despite enjoying the lion’s share of possession and chances, the Gabonese striker's brace proved to be the difference at Wembley.
Aubameyang tucked home at the back post just before the 20-minute mark after a deep cross from Nicolas Pepe on the right.
And he was on hand once again with 20 to play, racing on to a swift counter attack before finishing impressively under Ederson to double the Gunners’ lead.
But Pep Guardiola’s men will feel they had the chances to reach a second consecutive FA Cup final on another day.
It was a similar story of so close yet so far once again on the hour when Kevin De Bruyne’s near-perfect free kick crashed into the side netting from 20 yards out.
And minutes later Sterling could not quite adjust his body in time to guide home a close-range header from a corner.
But it was not to be, and Mikel Arteta’s Gunners weathered the City storm before Aubameyang’s 71st minute sucker punch booked their place in the final.
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