Matej Vydra came off at half-time during the 2-2 draw with Derby complaining of a slight muscle problem but boss Slavisa Jokanovic expects him to be fit.
Fellow striker Fernando Forestieri (knee) and midfielder Almen Abdi (hamstring) missed the Good Friday clash but could also be in contention to return.
However, defender Marco Motta is suspended following his red card against the Rams while Joel Ekstrand and Sean Murray (both knee) are long-term absentees.
Middlesbrough boss Aitor Karanka could make changes despite moving top of the Championship with a win over Wigan.
The congested fixture schedule means Jelle Vossen returned to the line-up on Good Friday, but Lee Tomlin is pushing for a recall to partner Patrick Bamford in attack.
New signings Fernando Amorebieta and Dwight Tiendalli watched from the bench but Karanka has hinted they may be handed their debuts against the Hornets.
Jonathan Woodgate came through unscathed after replacing Emilio Nsue despite a toe injury, while Ryan Fredericks (hamstring) and central defender Daniel Ayala (thigh) are still short of fitness.
Watch Watford v Middlesbrough live on Sky Sports 1 at 12.30 on Easter Monday.