The hosts took the lead in the 34th minute when striker Keinan Davis was presented with a tap-in after Hassane Kamara’s low cross.
Defender Aji Alese then drew Tony Mowbray’s side level on the stroke of half-time after his effort sneaked over the line.
Watford started strongly in the second half and retook the lead when Luke O’Nien headed the ball into his own net, yet Black Cats substitute Jewison Bennette scored a dramatic equaliser three minutes from time.
Our Sunderland writer Phil Smith has dished out his player ratings from Vicarage Road:
9. Jack Clarke - 6
Struggled to get into it early on but improved as half time approached and that played a big part in the equalising goal. Looked to have scored a brilliant volley just before he came off, only for it to be ruled offside. 6 Photo: Martin Swinney
10. Patrick Roberts - 8
Assisted the second goal and was arguably the driving force in the comeback after a sluggish start to the game. Constantly drove into space to drag his side up the pitch and occupy defenders. It was a big contribution yet again. What a week for him. 8 Photo: Martin Swinney
11. Alex Pritchard - 6
Work-rate was excellent from start to finish, trying to put pressure on the ball as Watford largely dominated possession. 6 Photo: FRANK REID 2022
12. Amad Diallo (sub) - 8
Changed the game with an excellent cameo, drifting out into space on the right. Would have had an assist had Clarke been able to stay onside. 8 Photo: Frank Reid