It will be the Brazilian's 100th City appearance and he will look to make another significant impact having scored the winner in the semi-final last month.
That's the only change Pep Guardiola makes to the side that beat Brighton last weekend to secure back-to-back Premier League titles.
Kevin De Bruyne is again fit enough to start among the substitutes, but Fernandinho, a vital component of City’s success this season, remains sidelined with a knee injury he picked up in the Manchester derby.
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XI: Ederson, Walker, Kompany, Laporte, Zinchenko, Gundogan, Silva, Bernardo, Sterling, Mahrez, Jesus
Subs: Muric, Danilo, Stones, Aguero, De Bruyne, Sane, Otamendi
Guardiola rarely deviates from 4-3-3 and today is no exception.
Ederson, outstanding throughout the campaign, starts in goal, with Vincent Kompany and Aymeric Laporte offering protection in front of him. Those two have formed a fine partnership in the final stages of this season, a key element of us getting over the line in the Premier League.
Kyle Walker and Oleksandr Zinchenko will provide additional attacking width in support of Mahrez and Raheem Sterling on the wings.
Ilkay Gundogan, whose form since the turn of the year has been exceptional, continues to anchor midfield in Fernandinho’s absence. David Silva and Bernardo Silva will provide guile just ahead of him. Jesus leads the line up front.
City will look to control the ball and dominate possession, with a focus on attack. We've scored 163 goals already this season, which only underlines our intent going forward.
Move the ball quickly and effectively when we have it; work had to recover the ball when its lost. It's a simple paradigm on paper.
Watford are on a 10-match losing streak against Manchester City in all competitions and are winless in 15 since a 1-0 victory in the second tier back in March 1989.
This will be the first FA Cup final between two managers of the same nationality since 2008 (Dave Jones and Harry Redknapp). It's only the second time it has happened with non-British managers: Frenchmen Arsene Wenger and Gerard Houllier went head-to-head in 2001.
Either Pep Guardiola or Javi Gracia will become the third Spanish manager to win the FA Cup, emulating Rafael Benitez (2006, Liverpool) and Roberto Martinez (2013, Wigan).
City are aiming to become the first team to win the domestic treble in England, having already won the Premier League title and League Cup this season.
Pep Guardiola could become just the eighth manager to win the English top flight, League Cup and FA Cup in his career, after Bill Nicholson, Don Revie, Joe Mercer, Sir Kenny Dalglish, George Graham, Sir Alex Ferguson and Jose Mourinho. Mercer achieved the feat with Manchester City.
They would become just the fourth team to win both major domestic cup competitions in the same season after Arsenal in 1992-93, Liverpool in 2000-01 and Chelsea in 2006-07.
Manchester City have won five and lost five of their 10 previous FA Cup finals.
Sergio Aguero has scored 10 goals in just seven appearances against Watford in all competitions, including two hat-tricks.
Watford's only previous FA Cup final appearance came in 1984, when they lost 2-0 to Everton.
Their 35-year wait for a second FA Cup final is the longest since 1967, when Chelsea appeared 52 years after first featuring in 1915.
The only four clubs to reach the final on multiple occasions without ever winning it are Leicester City, Birmingham City, Crystal Palace and Scottish team Queen's Park.
This season, Watford became only the second team in Premier League history to win their first four games but finish outside the top seven, emulating Charlton Athletic in 2005-06.
The Hornets had the oldest average starting XI in the Premier League this season: 28 years and 323 days.