- Young scores pretty pair (video)
- Martial makes it 3-0
- Rojo concedes PK
- Lingard solo dribble ends it
United is now five points back of Man City, which plays Wednesday versus Southampton.
Watford fails to reach the Top Four, and remains eighth with 22 points.
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And Watford was largely on the front foot for the first quarter hour, as Will Hughes continued his prominent role in the team and Richarlison remained a challenge for the opposition.
Young gave United a second goal in as many matches, this one credited to him, as he hit a shot from the left that beat Heurelho Gomes to the near post.
Paul Pogba won a 24th minute free kick during a 50-yard dribble through the heart of the midfield. Abdoulaye Doucore saw yellow, and Young stepped to the plate with a fantastic, swerving free kick goal.
Martial added a third in the 32nd minute, running to the top of the 18 to hit a low shot to the left of a diving Gomes.
Romelu Lukaku‘s 45th minute rip was stopped by a Gomes dive, and the keeper popped up to stop Jesse Lingard’s rebound.
Richarlison missed a header just before the halftime whistle.
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Lukaku had a sadly funny miss in the 75th minute. Cued up alone with an empty net, he dribbled out of a chance to make it 4-0 to compound his struggles and confound his supporters.
Deeney then got higher than Chris Smalling to head on goal.
Watford continued to control play, and Marco Silva‘s men pulled within one when Doucoure connected with a cross. The Hornets would have seven minutes to find an equalizer.