Match ends, Watford 3, Stoke City 2.
Ismaila Sarr scored a stoppage-time goal as Watford won for the first time in four Championship games by beating Stoke.
Sarr found the bottom corner from Ken Sema's pass to settle a game in which the lead changed hands three times.
Stoke were given early impetus when Steven Fletcher converted Nick Powell's low cross.
But Watford drew level when Tom Cleverley's shot was judged to have crossed the line after being tipped on to the bar by keeper Angus Gunn, who was himself then barged over the line by Joao Pedro after gathering the bouncing ball.
Brazilian teenager Pedro made it 2-1 from the spot after Gunn was penalised for bringing down Sarr, who netted the decider after Powell scored his third goal in five games to bring Stoke level with a powerful low strike.
The victory lifted Vladimir Ivic's side into fourth place, with Stoke - who had won on six of their eight previous league visits to Watford - slipping down to 11th.
Ivic resisted the temptation for major changes despite Saturday's disappointing performance at Barnsley, but brought in Christian Kabasele for William Troost-Ekong in defence.
It only took Stoke two minutes to find a way through, though, as Fletcher applied the finishing touch following a clever short corner routine involving three team-mates.
Watford dominated possession but lacked a cutting edge until Cleverley's controversial equaliser - his second goal of the season
Fletcher glanced a header wide for Stoke after the break but Gunn was penalised when Sarr ran onto a missed clearance and tried to go round him, and Pedro found the corner from the spot.
It was his final act as he and Cleverley were replaced by Andre Gray and James Garner and the former could have made it three when he headed wide from Kiko Femenia's cross before Powell appeared to have earned Stoke a point, only for Sarr to pick his spot from the edge of the box and make it four wins out of five for Watford at home.
Watford boss Vladimir Ivic:
"The first moment I couldn't see exactly what happened but at half-time I heard that maybe we were lucky with the (first goal) decision.
"But we cannot speak just about this goal. If we speak generally about the game we didn't start well. We started to play after the goal of our opponent and this is something we need to fix.
"After that we were the dominant team and I believe we have made progress if you speak about possession, attacking moments and crossing.
"We can do better and our target will be to do that. We need to be focused from the first second to the last of every game."
Stoke manager Michael O'Neill on Tom Cleverley goal:
"We didn't feel it was a goal. I've seen the replays and it's clear the initial shot did not cross the line.
"The officials have to look at the events as well as the technology. On this occasion the technology didn't help them in any way - when you see the events it was a very harsh decision against us.
"We felt there was a foul on Angus after he gathers the ball so if the technology is triggered post the goal obviously you would expect that is not a goal.
"We are disappointed with the decision but it is not going to change now and we will just have to move on from it."
- 14ChalobahBooked at 56minsSubstituted forHughesat 89'minutes
- 29CapoueBooked at 90mins
- 8CleverleySubstituted forGarnerat 62'minutes
- 10João PedroSubstituted forGrayat 62'minutes
- 1GunnBooked at 61mins
- 14SmithSubstituted forVokesat 74'minutes
- 13ObiBooked at 79mins
- 21FletcherSubstituted forBrownat 66'minutes
- 25PowellSubstituted forCousinsat 86'minutes
- 40Nna Noukeu
- Andy Davies
- Shots on Target
Second Half ends, Watford 3, Stoke City 2.
Ismaila Sarr (Watford) wins a free kick on the left wing.
Foul by Tyrese Campbell (Stoke City).
Attempt saved. Harry Souttar (Stoke City) header from the centre of the box is saved in the bottom right corner. Assisted by James McClean with a cross.
Etienne Capoue (Watford) is shown the yellow card.
Foul by Will Hughes (Watford).
Jordan Thompson (Stoke City) wins a free kick in the attacking half.
Goal! Watford 3, Stoke City 2. Ismaila Sarr (Watford) right footed shot from the centre of the box to the bottom left corner. Assisted by Ken Sema.
Attempt blocked. Will Hughes (Watford) left footed shot from outside the box is blocked. Assisted by Ismaila Sarr.
Attempt missed. Ismaila Sarr (Watford) header from a difficult angle on the left is close, but misses to the left. Assisted by Ken Sema with a cross.
Offside, Stoke City. Jordan Thompson tries a through ball, but Harry Souttar is caught offside.
Foul by Ben Wilmot (Watford).
Tyrese Campbell (Stoke City) wins a free kick on the right wing.
Substitution, Watford. Will Hughes replaces Nathaniel Chalobah.
Attempt blocked. Kiko Femenía (Watford) right footed shot from outside the box is blocked.
Corner, Watford. Conceded by Jacob Brown.
Substitution, Stoke City. Jordan Cousins replaces Nick Powell.
Attempt missed. Nick Powell (Stoke City) right footed shot from the centre of the box is too high. Assisted by Tyrese Campbell.
Goal! Watford 2, Stoke City 2. Nick Powell (Stoke City) right footed shot from the centre of the box to the bottom left corner. Assisted by Tyrese Campbell.
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