Arsenal strolled to a much-needed win as Shkodran Mustafi, Pierre-Emerick Aubameyang and Henrikh Mkhitaryan saw off Watford 3-0 at the Emirates Stadium and Petr Cech kept his 200th Premier League clean sheet.
The Gunners had a fine early chance to take the lead at a sparsely-populated Emirates when Mesut Ozil found Aubameyang but the striker fired straight at keeper Orestis Karnezis.
Richarlison then shot into the side netting for Watford before Arsenal made the breakthrough after eight minutes when Ozil's cross was headed powerfully home by Mustafi.
The visitors responded well and Abdoulaye Doucoure blasted an effort that Cech parried before the Gunners came forward once more and an Ainsley Maitland-Niles cross was headed over by Alex Iwobi.
Watford should have been level shortly before the half-hour when Cech pushed away a Richarlison free kick and Roberto Pereyra, following up, thrashed an effort wildly over when he had time to take a touch and then shoot.
Karnezis then denied Ozil as Arsenal pressed for a second goal but, with half-time approaching, back came Watford and Kiko Femenia's cross was diverted onto the roof of his own net by Rob Holding.
There was still time for Cech to make another save, repelling Richarlison's header, as the Gunners went into the break with a much-needed lead.
Granit Xhaka had a long-range shot stopped by Karnezis as Arsenal began the second half brightly, and moments later Cech was relieved as a Watford corner flew dangerously across his six-yard area with no visiting player able to get a touch.
The visitors were showing plenty of purpose, giving Arsenal's defenders little time on the ball, and Femenia saw a volley blocked before Mustafi fouled Richarlison as he attempted to break clear and picked up a yellow card for his troubles.
The Watford pressure proved to be in vain when, after 59 minutes, Arsene Wenger's side doubled their lead through Aubameyang, who rounded the keeper to score with a low finish after Mkhitaryan had put him through.
Within two minutes the Hornets had a route back into the match when Maitland-Niles brought down Pereyra inside the area -- but Cech made a fine save to keep out Troy Deeney's penalty.
Watford took off Femenia and replaced him with Will Hughes, and moments later Arsenal could have had a penalty when Adrian Mariappa clattered Mkhitaryan as he crossed but the referee waved play on as the ball just eluded Aubameyang in the middle.
Jose Holebas was then booked for a heavy challenge on Mkhitaryan and Arsenal made a change, bringing on Danny Welbeck for Iwobi, with Watford then bringing on Stefano Okaka for Pereyra.
The home side made another change as the game headed for its final 15 minutes, Mustafi coming off to be replaced by Calum Chambers.
And with 77 minutes gone they made absolutely sure of victory when Ozil crossed and Aubameyang set up Mkhitaryan, whose strike made it into the corner despite Karnezis getting a touch.
That was the Armenia international's final contribution to the match, Jack Wilshere coming on to replace him as Arsenal played out the final stages in complete comfort, Welbeck having a late strike saved as they looked for a fourth.