Arsenal’s £105m man Declan Rice delivered the decisive goal, brilliantly controlling a corner at the back post before blasting a shot off 35-year-old Jonny Evans and past Andre Onana.
Evans appealed for a foul from the cross but Rice’s celebrations into the crowd were an iconic moment, adding another remarkable chapter to this Premier League rivalry.
Moments later Jesus sealed it, breaking away and leaving Diogo Dalot and United on the floor.
Last season it was Eddie Nketiah dealing the injury-time knockout blow to United. This time it was a Rice-Jesus one-two.
Earlier, United thought they’d won it themselves in the final minutes when Alejandro Garnacho broke free to score but a close VAR offside call denied him his moment.
In the first half, Arsenal captain Martin Odegaard had come up with an instant response to Marcus Rashford’s counter-attack goal, hitting the net 35 seconds after the restart.
Arsenal thought they’d been handed a chance to go in front on the hour mark when Kai Havertz went down in the box and a penalty was awarded. But replays showed it was the German looking for contact with Aaron Wan-Bissaka and it was overturned by a VAR check.