The Gabonese striker struck in the 19th and 71st minutes as Arsenal coach Mikel Arteta gained bragging rights over Pepe Guardiola, his old mentor at City.
Manchester City, aiming for a domestic cup double having won the English League Cup before the lockdown, could not make the most of the lion’s share of possession as Arsenal defended stoutly and looked ever dangerous in counterattack.
The opening goal came in this fashion as the Gunners launched a sweet passing move from inside their own half and Nicolas Pepe found Aubameyang, who finished neatly at the far post, all the more creditable having missed another chance moments before.
The same pattern continued with City unable to capitalize on its pressure before Arsenal’s Shkodran Mustafi forced a fine save from City keeper Ederson just before the break.
Breakaway second goal
The near misses came back to haunt the cupholder as Arsenal broke forward and Aubameyang raced onto Kieran Tierney’s pass to shoot home his second past Ederson.
At the end it was a smiling Arteta, formerly an assistant manager to Guardiola at City, who was celebrating in a cavernous and empty Wembley, normally filled to capacity for such a big match.
Luiz paid tribute to Arteta’s influence since taking over at the North London club late last year, with a 2-1 victory over new Premier League champion Liverpool earlier this week further sign of progress.
“We have an amazing coach but we can’t go from 0 to 100. We are improving. The spirit was great and I’m happy for the team because they deserve it,” Luiz told BT Sport.
“We have a final to play this season and we will try and win a title for this club because this club deserves to win a trophy,” the Brazilian added.
The cup final is set for August 1 and Arsenal will face the winner of the second semifinal on Sunday between Chelsea and Manchester United.
City will now focus on its Champions League dream with the second leg of its last 16 tie against new Spanish champion Real Madrid next month.