Kevin De Bruyne, Ilkay Gundogan, John Stones and Kyle Walker are all back in contention
Manager Pep Guardiola claimed his squad were facing an “emergency” ahead of their midweek win at Aston Villa as they were hit by injury, illness and suspension problems.
That emergency now seems to be over with playmaker Kevin De Bruyne heading a host of players that could return at Vicarage Road.
With Jack Grealish and Phil Foden having made the bench at Villa Park and Aymeric Laporte available again after suspension, only long-term casualty Ferran Torres is still out.
Guardiola said: “Except Ferran all of them are ready to travel to London.
“It is much better. I said before the game against Aston Villa we need everyone and it is much better to have everyone.”
The top three in the Premier League of Chelsea, City and Liverpool have opened up a gap from the rest over the last couple of weeks but Guardiola is wary of the threat of Watford.
New manager Claudio Ranieri, the veteran Italian who guided Leicester to the title in 2016, has brought fresh enthusiasm to the club and they scored a stunning 4-1 win over Manchester United a fortnight ago.
Guardiola said: “Football has to be grateful we still have important people like Claudio Ranieri. What he’s done in his career is amazing.
“Of course Leicester is the benchmark but with what he has done in Spain, 意大利, 法国, everywhere, I admire this type of person.
“After they lost to Liverpool he was confident to say, ‘If they follow me we will win’. I admire a lot that passion and energy. It will be a pleasure to see him again.
“I know results against him are not always good. I know exactly what they want to do but what they do they do it really well.
“We have to be careful and make another good performance.”