Sunderland were shoved another step closer to relegation as Miguel Britos fired Watford to a 1-0 victory.
Uruguayan defender Britos headed his first Hornets goal to leave David Moyes' strugglers still seven points adrift of safety and with games running out.
Watford had been frustrated by Sunderland keeper Jordan Pickford, who made a string of fine saves to deny M'Baye Niang and Abdoulaye Doucoure.
But Pickford could not prevent Britos pouncing after a goalmouth scramble to condemn Sunderland to another defeat.
One goal is all you need to beat the Black Cats at the moment, as they have now not scored in their last five matches and not even Jermain Defoe, fresh from his England renaissance, looked likely to end their drought.
By contrast, a first win in five matches should ease Watford's fears of being dragged into trouble.
Pickford was quickly into the action for Sunderland, the youngster palming Niang's shot away before making a stunning, diving save to scoop Doucoure's follow-up over the crossbar.
Stefano Okaka should have put Watford ahead with a free header which he planted over, before Etienne Capoue curled narrowly wide.
Watford's injury curse struck again shortly before half-time when Younes Kaboul pulled up with a hamstring injury.
Moments later Adnan Januzaj's shot took a big deflection which wrong-footed Heurelho Gomes but, fortunately for the Watford goalkeeper, flew just wide.
Pickford then had to get down sharply to block another Niang effort at the near post, and from the corner Craig Cathcart headed straight at the Black Cats keeper.
The breakthrough arrived in the 59th minute, and it was hardly a goal straight off the training ground.
Okaka met Tom Cleverley's corner with a header which Sunderland forward Fabio Borini inadvertently nodded on to his own crossbar.
The ball flew out to Cathcart, who headed it back across goal for Britos to bundle in at the far post.
Moments later substitute Isaac Success burst through one-on-one with Pickford but the keeper spread himself well to block the shot with his leg.
Januzaj was then replaced to the sound of sarcastic jeers from the away support, who were clearly not impressed with his efforts.
Jose Holebas almost doubled Watford's advantage with a 20-yard drive which cleared Pickford's glove but also the crossbar.
Instead Sunderland pressed for an equaliser, but Gomes kept out Borini's long-range effort to secure the points and deepen the gloom on Wearside.