Sebastian Prodl is suspended while Christian Kabasele, Craig Cathcart and Younes Kaboul are all out injured.
Manchester City captain Vincent Kompany should be fit despite being substituted during the 3-1 win over West Brom.
John Stones has also recovered from a groin strain and could replace Nicolas Otamendi in defence.
Steve Wilson: "Pep Guardiola's been saying some interesting things this week. Firstly that his side's performance this season would have got him sacked at the kind of club he's been accustomed to working at.
"Then he asked an interviewer to give him one good reason to think that the English league is anything special compared to Spain, Italy and Germany.
"I'm certainly not saying that Guardiola is wrong - just that it's odd that he was willing to say this stuff. You might interpret it as a pointed signal to those he works with at City to up their game if they want to get to his level.
"Speaking of managers, Walter Mazzarri has been told to pack his bags with Watford issuing a statement remarkable only for its brevity.
"The Hornets are on their longest losing streak in nine years - should they lose again on Sunday it will be their longest for 44 years. Enough said."
Twitter: @Wilsonfooty
Watford head coach Walter Mazzarri: "I would like to thank the main characters of this season - the players and the fans.
"Our fans have always been extraordinary with their participation and with their fantastic passion for the whole season.
"Also I thank the players, who have always given 200 per cent of what they had, always going further and pushing their limits."
Manchester City manager Pep Guardiola: "It's a crucial game for us absolutely - a final. It's in our hands. We have to go there and win. We have won three in a row but we still have 95, 96 minutes to fight.
"Watford have had a good season. They are safe. We have to be careful.
"We are going to make changes [in the summer]."
I had been wondering for a while what was going to happen to Watford boss Walter Mazzarri, and it was no surprise when it was announced this week that he will be leaving.
I think the Hornets will play well in his farewell game but I still think Manchester City will get the win they need to secure third place.
Prediction: 0-3
Lawro's prediction v rock band Royal Blood.
Head-to-head
Watford
Manchester City
SAM (Sports Analytics Machine) is a super-computer created by @ProfIanMcHale at the University of Salford that is used to predict the outcome of football matches.
Watford could be without up to six central defenders, with Adrian Mariappa (knee) and Miguel Britos (calf) facing late fitness tests.