Wilfried Zaha tucked his penalty past Ben Foster after Hassane Kamara's handballWatford have been relegated from the Premier League after Wilfried Zaha's first-half penalty secured a deserved victory for Crystal Palace at Selhurst Park.
Defeat by Burnley last week had left the Hornets 12 points adrift of safety with four games remaining and Palace sent their former manager Roy Hodgson's side straight back down to the Championship with a dominant display.
The Eagles controlled the contest from the outset and went ahead when Zaha confidently swept his 31st-minute spot-kick past Ben Foster after Hassane Kamara had used his arm to block Michael Olise's back-post header.
Watford never looked like scoring and their misery was compounded when Kamara, already booked for that handball, was dismissed when his push on Olise produced a second yellow card.
It is the second time Watford have dropped out of the top flight in the past three seasons. The manager-less Hornets also went went down on the final day of the 2019-20 campaign before securing an immediate return under Xisco Munoz.
The identity of the coach who will be tasked with emulating Munoz's achievement is still unknown, however, with Hodgson set to retire from top-level management when his contract at Vicarage Road expires at the end of the season.
Relegation represents a bitter final chapter in 74-year-old Hodgson's time as a manager, which has included spells at 17 clubs - including Palace - in eight countries, plus four international sides, during a 46-year career.
Palace's win - which takes them to within five points of their highest-ever tally in a Premier League season - confirmed what many Watford fans had already accepted after last week's loss to fellow strugglers Burnley.
While they briefly boosted their survival hopes with victory at Southampton in March, a fourth Premier League relegation was effectively sealed with a run of five straight defeats before the trip to Selhurst.
Watford's misery was compounded when Kamara was shown a second yellow card for a foul on OliseWatford never really got going as Palace took control early on. France Under-21 winger Olise, one of five players recalled by Eagles boss Patrick Vieira, created the home side's first chance after five minutes when Marc Guehi headed his teasing cross over the bar.
Olise was also involved in the first-half's key moment when his header from Eberechi Eze's left-wing cross struck Watford full-back Kamara's outstretched arm.
Graham Scott pointed to the spot, and while Kamara claimed Olise had pushed him in the back, a VAR review upheld the referee's decision, allowing Zaha to add to the double he netted in Palace's 4-1 win over Watford in February.
While Watford needed to score twice, it was Palace who looked like grabbing the game's second goal with Odsonne Edouard almost netting a superb solo goal just after the hour, dancing his way through the visitors' defence before hitting the post from a tight angle.
With Kamara sent off on 68 minutes, Palace cruised to victory as the game - and Watford's stay in the division - ended with a whimper.
Line-ups
Crystal Palace
Formation 4-3-3
1Butland
17Clyne16Andersen6Guéhi2Ward
23Gallagher12Hughes10Eze
7Olise22Édouard11Zaha
1Butland17Clyne16Andersen6GuéhiSubstituted forMitchellat 73'minutes2Ward23GallagherSubstituted forSchluppat 63'minutes12HughesBooked at 64mins10Eze7OliseBooked at 90mins22Édouard11ZahaSubstituted forMatetaat 83'minutesSubstitutes
3Mitchell4Milivojevic5Tomkins8Kouyaté9J Ayew14Mateta15Schlupp19Matthews20BentekeWatford
Formation 4-3-3
1Foster
21Femenía15Cathcart22Samir14Kamara
19Sissoko39Kayembe8Cleverley
23Sarr7King25Dennis
1Foster21Femenía15Cathcart22SamirSubstituted forTroost-Ekongat 78'minutes14KamaraBooked at 69mins19Sissoko39Kayembe8CleverleySubstituted forSemaat 52'minutes23Sarr7KingBooked at 84mins25DennisSubstituted forMasinaat 73'minutesSubstitutes
2Ngakia4Etebo5Troost-Ekong11Masina12Sema16Gosling26Bachmann27Kabasele28KaluReferee:Graham ScottAttendance:24,622Live Text
Match ends, Crystal Palace 1, Watford 0.
Second Half ends, Crystal Palace 1, Watford 0.
Michael Olise (Crystal Palace) is shown the yellow card for a bad foul.
Foul by Michael Olise (Crystal Palace).
Ken Sema (Watford) wins a free kick in the defensive half.
Attempt saved. Jeffrey Schlupp (Crystal Palace) left footed shot from the left side of the box is saved in the centre of the goal. Assisted by Will Hughes.
Will Hughes (Crystal Palace) wins a free kick in the attacking half.
Foul by Ismaïla Sarr (Watford).
Foul by Jeffrey Schlupp (Crystal Palace).
Ken Sema (Watford) wins a free kick on the right wing.
Attempt missed. Jean-Philippe Mateta (Crystal Palace) header from very close range is close, but misses to the left.
Attempt saved. Jean-Philippe Mateta (Crystal Palace) header from the centre of the box is saved in the bottom left corner. Assisted by Michael Olise with a cross.
Joshua King (Watford) is shown the yellow card for a bad foul.
Joachim Andersen (Crystal Palace) wins a free kick in the defensive half.
Foul by Joshua King (Watford).
Substitution, Crystal Palace. Jean-Philippe Mateta replaces Wilfried Zaha.
Attempt missed. Craig Cathcart (Watford) header from the centre of the box is just a bit too high. Assisted by Kiko Femenía with a cross following a corner.
Corner, Watford. Conceded by Tyrick Mitchell.
Foul by Jeffrey Schlupp (Crystal Palace).
Edo Kayembe (Watford) wins a free kick in the defensive half.
Player of the match
EzeEberechi Eze
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