First Nunes goal seals City's cup progress
Matheus Nunes's first Manchester City goal proved the difference as Pep Guardiola's team beat Watford 2-1 to progress to the Carabao Cup fourth round.
Tom Ince set up a nervy ending for the hosts at Etihad Stadium, but EFL Championship side Watford could not find a late equaliser to force a penalty shootout.
City got off to a quick start, helped by Ryan Porteous's loose backpass, as James McAtee pounced before Jack Grealish teed up Jeremy Doku for a pinpoint finish into the bottom corner after five minutes.
Kwadwo Baah thought he had equalised in the 21st minute, drilling his low shot into the far post, but he was penalised for a foul on debutant Kaden Braithwaite.
Rico Lewis then opened up Watford's defence with a driving run before laying it off to Nunes, whose low effort crept past Jonathan Bond to double City's lead before the break.
Ince cleared Savinho's effort off the line before the Brazilian also struck the inside of the post as City searched for a third, while Bond made impressive stops to deny Nunes and Grealish.
Yet it was Watford that struck next, Ince bending a lovely finish beyond Stefan Ortega, but the visitors failed to test City again after that.