Fans were delighted with the result and praised the performance of Mustafi on social media after the game.
That was a sweet moment for the home fans, as Deeney had questioned Arsenal's heart when the Hornets won the corresponding fixture in October. It's having a bit of cojones.
"When he gets on it and you give him a little bit of time to play, he can manoeuvre the ball so well".
"They all just backed off".
Understandably maybe, considering the country was in the midst of being battered by "Storm Emma", as well as the fact Arsenal's showing the League Cup final the Sunday prior was not exactly the most inspirational display.
'I remember very well every time he refused the biggest clubs to stay at Arsenal.
"It's been a while and I have to say it's never happened that I've had to wait 11 games for a clean sheet", Cech told the club's website.
"I'm buzzing for Petr to get over that milestone". Thus, worry not! As there are no issues with celebrating Petr Cech's latest record-breaking achievement: picking up his 200th clean sheet in the Premier League! It shows a huge level of motivation and intelligence, and he shows plenty of that.
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.
The Czech Republic and former Chelsea 'keeper also saved a penalty on his way to bringing up a 200th EPL clean sheet over the last 14 years.
Watford have now lost all five of their away Premier League matches in the month of March.
"Looks like you couldn't see today either @T_Deeney", wrote Bellerin, who missed the game through injury.
"We have still some work to do, but we are on a good way".
Few goalkeepers get the man-of-the-match award when their team wins 3-0. "We are not so far to the end of the season so, any injuries, you lose them for the rest of the season".
After beating AC Milan on Thursday, Arsenal kept the momentum going with a 3-0 win over Watford in the 30th round of the Premier League.
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