Arsenal headed into the game looking to return to winning ways in the top flight after their disappointing 1-0 loss to Everton last time out.
The Gunners took the lead in the 10th minute at Vicarage Road when Ben Foster’s clearance rebounded into the back of the net off the on-rushing Pierre-Emerick Aubameyang, who used his searing pace to catch the goalkeeper out.
Watford were then reduced to 10 men moments later when Troy Deeney was shown a straight red card for a dangerous challenge on Lucas Torreira.
Arsenal managed to hold firm and grind out an important away win which kept alive their hopes of finishing in the top four this season.
And former Manchester United defender Neville praised Aubameyang for his input on Monday night.
Neville told Sky Sports: “Ben Foster should deal with it, he’s an experienced goalkeeper. But you have to give credit to Aubameyang.
“He’s so sharp and so quick. It’s the speed of his acceleration that catches Ben Foster out, there’s no doubt about that.
“He [Foster] thinks he’s got loads of time. The speed of it was incredible and the intent [was too]. He wants that ball badly and he gets his rewards for it.
“That’s why he’s delighted with the goal. He probably does that 100 times a season and probably gets one moment like that – and it makes it all worthwhile.”
The result left Arsenal in fourth place in the table and a point behind third-placed Tottenham with five games left to play this season.
The Gunners will switch their attentions back to Europa League affairs on Thursday night when they take on Napoli in Italy for the return leg of their quarter-final clash, having won the first leg 1-0 at The Emirates last week.
Arsenal will then take on Crystal Palace at The Emirates in the Premier League on Sunday afternoon as they look to continue their push towards a top-four finish.
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