Middlesbrough's Justin Hoyte has been ruled out with a hamstring injury, while Gary O'Neil has been carrying a knock and will have a fitness test.
Joe Bennett (tonsilitis), Willo Flood (knee), Matt Kilgallon (back), Kevin Thomson (leg), Jonathan Franks (back) and Rhys Williams (pelvis) are out.
MATCH PREVIEW
Tipped by many to struggle this season, Watford have won their last two matches, are fifth in the table, and hammered Millwall 6-1 in a stunning away victory last time out. Only leaders QPR have scored more goals than the Hornets, who have netted 15 already this term.
All Malky Mackay's side are lacking is a home win. They will be out to claim their first of the campaign, while Middlesbrough will be looking for their first away victory - and goal - when they visit Vicarage Road.
After a poor start to their season, Boro have won their last two matches, but both of those victories were at home. On the road, they have suffered three consecutive defeats.
They may need to be on their guard in the early stages of Saturday's encounter, as Watford have scored four goals in the opening 15 minutes of matches this season - more than any other team in the division.
MATCH FACTS
Head-to-head
• This is the 25th league meeting of these clubs. Middlesbrough have won 10 of the previous matches and Watford nine, with five draws.
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• Boro have won on one of their last five visits to Vicarage Road.
Watford
• Watford are the only club in the top 16 without a home win in the Championship.
• Hornets boss Malky Mackay has fielded only 16 players in league matches this term - fewer than any other second-tier manager.
• Don Cowie has five goal assists to his name this season. Only QPR's Adel Taarabt beats that.
Middlesbrough
• A win for Middlesbrough would mean three consecutive league victories for the first time since August 2009.
• They are one of only two teams in the division yet to score an away goal. The other is Crystal Palace.
• Boro are averaging a goal per game, having scored a total of seven in their seven league games so far.
Source: BBC Sport
Source: BBC Sport