Alejandro Garnacho took advantage of a rare Manchester City mistake to give Manchester United the lead in the FA Cup final.
Pep Guardiola's men dominated much of the possession and limited United to a few efforts in a cagey opening 30 minutes.
Diogo Dalot played a long towards the edge of City's box and Josko Gvardiol shrugged off Garnacho before attempting to head it back to Stefan Ortega, who had already come off his line.
The Argentinian winger got in behind and guided the ball into an empty net to put Erik ten Hag's men a goal up.