Manchester United suffered their third defeat in eight days, as Watford handed Jose Mourinho his worst run of losses as a manager in over a decade.
Goals from Etienne Capoue, Juan Zuniga and a late penalty from Troy Deeney overwhelmed the visitors, who had earlier managed to draw level after a solitary strike from Marcus Rashford.
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Watford stun Manchester United
The Red Devils' terrible week concludes with defeat away to Watford.
Despite dominating possession, United were unsettled by Watford's harrying game, and went behind on 32 minutes after Manchester striker Martial, still groggy from an earlier clash of heads, was robbed by Watford's Britos.
Defender Daryl Janmaat picked up the ball and crossed for teammate Capoue to fire his fourth goal of the season for the Hornets.
![Hair-raising pace: Juan Camilo Zuniga of Watford races past Manchester United's Marouane Fellaini.](/web/20160921011029im_/http://www.smh.com.au/content/dam/images/g/r/j/4/m/o/image.related.articleLeadwide.620x349.grj4m2.png/1474234914684.jpg)
A half-time switch saw Wayne Rooney pushed further forward in pursuit of goals. This allowed United to settle, and then equalise, when Rashford scrambled the ball home after his header bounced back to him off a defender after 62 minutes.
Watford goalkeeper Heurelho Gomes denied Zlatan Ibrahimovic with a flying save, but United always looked vulnerable and Zuniga scored from a cutback by Roberto Pereyra less than a minute after coming on.
Zuniga was then brought down by Marouane Fellaini inside the area late on to allow Deeney to score from the spot.
A first home win of the @premierleague season, and a first #watfordfc win over @ManUtd since 1986. ✅⚽️ pic.twitter.com/z0rpUXQvhT
— Watford FC (@WatfordFC) September 18, 2016
![Off target: Marcus Rashford reacts after the final whistle in away loss to Watford.](/web/20160921011029im_/http://www.smh.com.au/content/dam/images/g/r/j/4/m/p/image.related.articleLeadwide.620x349.grj4m2.png/1474234914684.jpg)
Elsewhere, Harry Kane powered Spurs to a 1-0 win over Sunderland.
Crystal Palace hammered Stoke City 4-1 to move into the top half and send Mark Hughes' side to the bottom of the table.
James Tomkins, Scott Dann, James McArthur and Andros Townsend scored the goals as Stoke let in four goals for the third time in four Premier League matches.
Southampton moved out of the bottom three thanks to a 1-0 win over Swansea, Charlie Austin scoring the vital goal.
Reuters