Heurelho Gomes, Miguel Britos, Will Hughes and Kiko Femenia could all return for Watford. Stefano Okaka is also available and Troy Deeney is fitter than in his last outing, when he was hampered by an ankle problem.
Younes Kaboul (ankle), Christian Kabasele, Tom Cleverley (both hamstring) and Nathaniel Chalobah (knee) are still sidelined.
Leighton Baines (calf) has a chance of returning for Everton, but Eliaquim Mangala (knee) is out and Seamus Coleman (thigh) is a doubt.
Ramiro Funes Mori (lacking match fitness) is expected to be available once he has come through another PL2 match in the coming week.
Did you know?
This will be the 10th Premier League meeting between these two teams, Watford winning on only one occasion.
Everton have won only one of their last 21 PL away matches (D9 L11).
Following their 4-1 victory over Chelsea, Watford are aiming to win consecutive home PL matches for the first time since April 2017.
Oumar Niasse's seven PL goals this season have been worth seven points to Everton. In comparison, Romelu Lukaku’s 25 goals for the Toffees last term were worth nine points.
Club previews
Watford: Gracia: We are ready to attack
Everton: Allardyce eyes improved away form
Referee: Anthony Taylor
Assistants: Peter Kirkup, Constantine Hatzidakis
Fourth official: Kevin Friend