|Crystal Palace's James McArthur celebrates scoring their second goal with Scott Dann|
Trailing to Daryl Janmaat’s third-minute opener, Palace really should have been out of contention before halftime as Watford spurned several good chances to extend their lead.
The game exploded into life in the 87th minute though when Watford’s Tom Cleverley was red-carded for a bad foul and two minutes later Bakary Sako scrambled an equaliser after Wilfried Zaha’s shot had been saved by Heurelho Gomes.
Selhurst Park then went wild as Zaha showed great footwork before picking out James McArthur to score the winner.
Palace are now unbeaten in their last six league games and have moved up to 17th spot with 14 points, the first time they have been out of the bottom three all season.
Watford have now gone four games without a win.