Manuel Pellegrini's side will be looking to come home with all three points from Vicarage Road this weekend.
The Irons are still looking for their first win of the season after another forgettable game against Man City and a hard-fought draw away to Brighton & Hove Albion.
West Ham Correspondent Sam Inkersole has given his thoughts ahead of this weekend's tie.
Win, lose or draw?
Win. The Hammers need to to get off the mark and have a point to prove just two games in after being one of those teams tipped to break into the top seven this season.
They wrapped up last season in impressive style at Watford too with a 4-1 win. The Irons are 5/2 to win with thepools.com .
Who's a good bet for 1st scorer?
Sebastien Haller. Missed the last game against Brighton and will be back from injury for the Watford game. Look for him to get off the mark this weekend.
The French striker is 11/2 with thepools.com .
Who's on the naughty step? (first card)
If he plays for Watford then Abdoulaye Doucoure. If the Hammers play their midfield four of Anderson, Lanzini, Fornals and Wilshere then the Hornets midfielder could get overrun. Failing that, defender Jose Holebas as he is a walking yellow card.
A fair few names have been mentioned and thepools.com have placed 11/10 odds on over 3.5 bookings .
Who's on pens?
Mark Noble if he returns from injury. He could make the bench this weekend. Otherwise, Manuel Lanzini could be the one to step up. The prospect of Lanzini on penalty duty makes the 10/1 first goalscorer price even more attractive.
Will your team keep a clean sheet?
They might actually have a chance this weekend. Troy Deeney is out and there are fitness doubts over Danny Welbeck, Ismaila Sarr and Roberto Pereyra. It’s as good a chance for West Ham as they’ll ever have this season to keep a clean sheet.
Lukasz Fabianski to get his first clean sheet of the season is at 16/5 .
