Watford defender Adam Masina will undergo a scan to determine the extent of the thigh injury that forced him off in the midweek defeat to Chelsea.
Watford have no other new injury concerns, with seven first-team players remaining out.
Manchester City will assess the fitness of a number of players, including Ilkay Gundogan, Kyle Walker and John Stones.
Aymeric Laporte is available following suspension.
LAWRO'S PREDICTION
Watford were very lucky against Chelsea in midweek. The very least they deserved was a point, if not all three.
But now they have to try to raise their game again, against the defending champions.