Etienne Capoue returns from suspension for Watford's Premier League trip to West Ham.
The midfielder is available again after serving a three-game ban following his red card at Leicester on December 1.
Will Hughes (hip), Andre Gray (leg), Sebastian Prodl (knee) and Adalberto Penaranda (foot) remain sidelined for the Hornets.
Provisional squad: Foster, Cathcart, Kiko, Holebas, Kabasele, Sema, Doucoure, Quina, Pereyra, Deeney, Success, Capoue, Gomes, Mariappa, Masina, Wilmot, Chalobah, Deulofeu, Okaka.