Watford lead Blackpool at the break in their Championship clash thanks to a strike from Cristian Battocchio
The game started evenly but it was the visitors who threatened first as Matt Derbyshire fired an effort on the half-volley at goal, though Jonathan Bond was able to make the save.
Watford responded as Fernando Forestieri put his shot just wide when well positioned in the penalty area, and minutes later Jonathan Hogg put a header inches past the post after latching onto Ikechi Anya's cross.
The home side were dominating possession and took the lead when Troy Deeney lifted a cross into the area, where Battocchio was able to tap the ball into the net.
Just before the break, Blackpool were within inches of being level as Derbyshire's looping header looked to set to hit the back of the net until Bond got a hand to the ball and tipped it over.