Dan Gosling is in line to make his Watford debut when Bristol City visit.
The midfielder joined from Bournemouth last month and is now up to speed and available for selection.
Kiko Femenia is also in contention having missed the last two games with a knock but the fixture is likely to come too soon for Isaac Success, despite his return to training following a lengthy hamstring complaint.
Christian Kabasele (knee) misses out, as do first-choice goalkeeper Ben Foster (broken finger) and long-term absentee Tom Dele-Bashiru (knee).
Bristol City travel to Vicarage Road having lost their last four games in all competitions.
Dean Holden will be unable to call on on-loan defender Alfie Mawson, who has returned to Fulham to have a medial ligament tear in his knee assessed.
The likes of Adrian Mariappa, Henri Lansbury and Dan Bentley will be pushing for recalls having dropped out of the starting line-up at Bramall Lane.
Holden has no fresh injury concerns and could keep academy graduate Ryley Towler in the side after he made his debut in midweek.