Leicester defender Jonny Evans will be assessed after pulling out of Thursday's Europa League victory over Legia Warsaw with a thigh issue.
Ricardo Pereira is the latest addition to the Foxes' injury list, while James Justin is not yet ready to return.
Watford pair Ismaila Sarr and Nicolas Nkoulou are out with respective knee and hamstring injuries sustained during the victory over Manchester United.
Midfielder Juraj Kucka is available again after serving a one-match ban.
LAWRO'S PREDICTION
Watford boss Claudio Ranieri goes back to King Power Stadium with his old side Leicester struggling to find their feet.