Watford are going to Wembley to contest an FA Cup semi-final for the seventh time in their history after Andre Gray came off the bench to score the winner and seal a 2-1 victory over Crystal Palace at a jubilant Vicarage Road.

It took a while for the Hornets to find their rhythm in the first half but when they did they produced a fine display in which every player, to a man, contributed to very positive effect.

And a spell of seven minutes or so of pressure deservedly culminated in the home side taking the lead when, following a corner, Etienne Capoue was able to divert the ball home.

While the lead just was one goal though, the outcome was always in the balance and a mistake from Adrian Mariappa enabled Palace to get back on terms when Michy Batshuayi capitalised.

But two minutes after replacing Will Hughes, Gray was to be the man who came up with the goods yet again, getting on the end of a superb pass from Roberto Pereyra to score Watford’s winner for a third consecutive home game.

Javi Gracia made eight changes to the side that was beaten 3-1 at Manchester City, reverting very much to his tried and tested line-up.

Heurelho Gomes, as expected, maintained his record of playing in every cup tie this season while, perhaps surprisingly, Kiko Femenia was preferred to Daryl Janmaat at right-back.

Crystal Palace also came into the tie off the back of a defeat, a 2-1 home reverse to Brighton & Hove Albion, and Roy Hodgson made three alterations to his starting XI and was forced to do without his star man.

Wilfried Zaha was ruled out of the contest with a muscle problem, while half of the defence which started against the Seagulls was also absent in Scott Dann and Patrick Van Aanholt.

Martin Kelly came into the reshuffled backline, with Cheikhou Kouyate and Max Meyer also promoted into the starting line-up, while Jeffery Schlupp moved to left-back.

Watford were made to attack the Rookery in the first half, but with their fans in superb voice from the outset they sought to make a positive start. But their opponents were also in the mood early on as well, with James Tomkins forcing Gomes into the first save of the match, the keeper diving to his right to hold at the second attempt, following good work on the left by Andros Townsend.

The opening 10 minutes were predictably frenetic though, with neither side able to settle into a real rhythm, with a strong and gusty wind also making life tricky on the pitch at times.

It took the Hornets until the 17th minute to muster their first attempt of the contest but it was a good one; Troy Deeney and Hughes battling to win back possession on the right side of the area before Gerard Deulofeu was able to wriggle his way into space and hit a drive from a tight angle which Vicente Guaita had to block at his near post.

The Palace keeper was given a moment of anxiety soon after by a quick Gomes clearance which was helped on its way by the wind. Under pressure from the advancing Deulofeu, Guaita could only clear as far as Pereyra, but the Argentinian’s cross was unable to pick out Hughes in space on the right side of the area.

Watford kept the pressure on as a Jose Holebas corner from the left went right through the penalty appeal without either side getting a touch on the ball, before Hughes played in a couple of dangerous deliveries from the right.

Some smart footwork from Deulofeu was next to leave Palace flummoxed, with the Spaniard releasing Deeney on the right, only for Kelly to get in the way of the skipper’s attempted pull back finding its way back to the Spaniard.

But Watford did not have long to wait for their pressure to count.

Again it came from a Holebas corner, this time from the right, and after Deeney had gone up to challenge Guaita, the ball cannoned back into the heart of the area where Capoue stuck out his right leg to divert the ball into the net to spark bedlam in three-quarters of the ground.

Watford had Palace where they wanted them and soon after they nearly tightened their grip even further when Deulofeu was released on the right side of the area and he advanced before hitting a rising drive which Guaita did well to tip over.

Luka Milivojevic picked up the game’s first yellow card in the 36th minute for a foul on Hughes and another free-kick could have had Palace in further trouble soon after. Deulofeu struck it well enough from around 30 yards out to the left of centre, getting the ball up and over the wall but Guaita was able to get across to hold.

There were some worrying moments for the Hornets though, when Holebas came off worse after challenging Townsend and was in clear pain holding his left ankle. But after receiving some treatment and initially gingerly taking a few steps he was able to continue.

The Hornets left-back was soon back into the action though, shadowing Wan-Bissaka before the ball was lifted through to the right edge of the are where Meyer caught it on the volley but Gomes was not unduly troubled.

Watford deservedly took their lead into the break but shortly before the break came one moment that summed up their desire.

The Hornets were caught with bodies up field when an attack broke down, but the unlikely figure of Deulofeu sprinted back to not only fill in at left-back, but successfully challenge James McArthur.

Although Holebas did make it through to half-time following his injury, he did not re-emerge after the interval and was replaced by Adam Masina.

Watford were soon back into their attacking stride in the second half though, thanks to the ingenuity and quality of Deulofeu.

The Spaniard controlled an awkward ball on his chest, beat an opponent with a lovely flick before advancing to the left side of the area where he stood up a cross that was just too high for Abdoulaye Doucuoure.

Soon after though, Palace were to win a corner which wasn’t particularly well struck and Meyer didn’t get the firmest of contacts on his header. But it was on target and heading inside the far corner after Kouyate ducked under it until Gomes, who was unsighted, dived late and stuck out a big right glove to claw the ball away.

Palace began to up the ante as they looked for a way back into the game thereafter, with Masina receiving the Hornets’ first yellow card for upending Meyer in the 57th minute. Townsend went for goal from the resultant free-kick to the right edge of the area, but Gomes was equal to it and tipped over.

Watford had been defending well, but their record of not conceding in the competition was to be ended by a costly mistake from Mariappa in the 62nd minute.

There didn’t appear to be any immediate cause for concern when a Gomes pass out was nodded back to the Hornets defender, who appeared to have more time than he thought and was closed down by Batshuayi, who broke clear and calmly placed his finish across the Watford keeper and into the far corner to equalise.

The Hornets had not been as cohesive going forward since the interval, but Deulofeu did have an opportunity midway through the second half when he chanced his arm with a curler from the left side of the area which Guaita comfortably held.

Some more slack play at the back could have been punished in the 72nd minute when Masina was caught in possession by Batshuayi, who cut the ball back into the area for Meyer, but he was crowded out and Doucoure was able to clear.

The next big opening was to fall Watford’s way two minutes later though, when Deulofeu spread play out to Masina on the left, his first-time deep cross was dropped by Guaita, but the keeper managed to recover to block Pereyra’s follow-up. However, the former Juventus man was given a second bite at the cherry and he picked out a stretching Doucoure, who was unable to direct the ball inside an unguarded back post.

Hughes’ afternoon was brought to a premature end in the 77th minute when he made way for Gray – and it was a change that worked an absolute treat.

There wasn’t too much on when a Palace clearance was headed back in the direction it came but Pereyra did superbly to win the ball initially, before backing himself to win it again as he kicked it into space on the left. Then once he got there, he dinked a superb pass in behind the defence where Gray had timed his run to perfection and stabbed the ball inside Guiata’s near post to make it 2-1.

After successfully repelling a Milivojevic free-kick, the Hornets weren’t far away from scoring the tie-clinching third when Deeney let fly from outside the area and Guaita did well to save, recovering to beat Deulofeu to the follow-up.

Soon after, the Palace keeper pulled off an even better save to keep out a Craig Cathcart header after a Watford corner had been allowed to bounce in the area.

After Christian Benteke had replaced McArthur, Deulofeu was rightly afforded a standing ovation when he made way for Tom Cleverley as the Hornets sought to see out the four minutes of stoppage time.

However, they had to survive one last scare when some uncertain defending saw the ball drop to Wan-Bissaka on the right but he dragged his shot wide of the far as Palace’s hopes died, leaving their opponents to celebrate the latest memorable day in their history.

Watford: Gomes; Femenia, Mariappa, Cathcart, Holebas (Masina 46); Hughes (Gray 77), Doucoure, Capoue, Pereyra; Deulofeu (Cleverley 89), Deeney. Subs not used: Dahlberg, Janmaat, Success Kabasele.

Crystal Palace: Guaita; Wan-Bissaka, Tomkins, Kelly, Schlupp; Milivojevic, Kouyate; Meyer, McArthur (Benteke 84), Townsend; Batshuayi. Subs not used: Hennessey, Ward, J Ayew, Wickham, Woods, Riedewald.

Bookings: Milivojevic for a foul on Hughes (36); Masina for a foul on Meyer (57).

Referee: Kevin Friend.