Emile Smith Rowe scored in his third successive Premier League match as Arsenal moved up to fifth with a 1-0 win against 10-man Watford at Emirates Stadium.
Bukayo Saka had a goal overturned for offside following a Video Assistant Referee review as Arsenal started brightly.
The Gunners squandered a great chance to break the deadlock on 36 minutes after Danny Rose had fouled Alexandre Lacazette in the area, but Ben Foster leapt to his right to save Pierre-Emerick Aubameyang's penalty.
Arsenal took the lead on 56 minutes when Smith Rowe fired into the far corner from the edge of the penalty area after a mazy run from Ben White.
Aubameyang's touch in from Martin Odegaard's 73rd-minute shot was ruled out for offside, before Joshua King nearly levelled for Watford when he hit the side-netting from a tight angle with the goal unguarded.
Juraj Kucka was sent off for a second bookable offence late on, as Arsenal held on to move up to 20 points, six behind leaders Chelsea.
Watford slip to 17th spot with 10 points.
See: Arsenal report | Watford report
Next fixtures
Arsenal: 20 Nov v Liverpool (A)
Watford: 20 Nov v Man Utd (H)
Match officials
Referee: Kevin Friend. Assistants: Adrian Holmes, Simon Beck. Fourth official: Martin Atkinson. VAR: Jarred Gillett. Assistant VAR: James Mainwaring.
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