Watford took a big step to making mathematically certain of their place in the Premier League for next season as Troy Deeney inspired them to a 2-1 victory at Crystal Palace this afternoon.

The Hornets skipper was in superb form throughout and having given the Hornets the lead with a penalty in the first half, he netted the winner with eight minutes remaining to take his side back up to eighth in the table and within four points of the fabled 40-point mark.

Having taken the lead through Deeney’s seventh goal of the season with a spot-kick after referee Bobby Madley had spotted Mile Jedinak hauling down the Hornets skipper at a corner, Watford were good value for most of the opening period.

They were firm in defence, keeping Wilfried Zaha and Emmanuel Adebayor largely quiet, were the better side in midfield and with Deeney in fine form as he linked play and probed, should have had more than one goal to their name against a Palace rearguard that looked nervy at times.

But just as it looked like the Hornets would take a deserved lead into the interval Palace equalised almost predictably through Adebayor, who could have been in the opposition camp; the striker sending a superb looping header over Heurelho Gomes to equalise.

The home side improved after the break and had chances to take the lead; Gomes twice coming to the fore again to thwart Adebayor and Yohan Cabaye.

But with eight minutes to go, Deeney capitalised after a Ben Watson cross had been glanced on to him and kept his composure to fire past Wayne Hennessey with his 90th goal since moving to Vicarage Road.

The Eagles though, will feel they were unfortunate not to get a point as Cabaye hit the post and Joel Ward headed another good opening over, either side of being reduced to ten men when Papa Souare was sent off for a dreadful challenge on Valon Behrami.

Following the disappointing performance in the 1-0 defeat at Tottenham Hotspur, Quique Sanchez Flores make four changes to the Hornets starting line-up, two of which were enforced due to injury.

Miguel Britos (leg) and Jose Manuel Jurado (calf) were sidelined while Mario Suarez and Almen Abdi dropped to the bench. There was absolutely no surprise that Deeney returned to the starting XI, Sebastian Prodl and Behrami were also included but the most fascinating of the quartet to come into the side was Nordin Amrabat, who made his Premier League debut.

Crystal Palace ended a run of five straight top-flight losses with a 1-1 draw at Swansea City last time out and Alan Pardew made just the one change as Connor Wickham, who was available again after suspension, came in for Chung-yong Lee to partner former Watford target Adebayor up front.

And it was the former Spurs striker who had the first sniff of an opening when he was played in by a through ball, but the assistant’s flag was already up for offside when Adebayor put his attempted lob on the roof of the net.

The opening ten minutes were largely scrappy though, with neither side able to establish too much of an early foothold, but with the Hornets arguably having settled the better of the two sides.

Cabaye sent an ambitious effort well over target from 30 yards but in the 15th minute the Hornets were given a great chance to take the lead thanks to a very good spot from referee Bobby Madley.

There was a sense of bemusement inside Selhurst Park when Madley pointed to the penalty spot following a Watson corner from the referee but replays showed Mile Jedinak clearly had both his arms wrapped around Deeney, who was pulled to ground as the ball came in.

The Hornets’ skipper didn’t need a second invitation, calmly sending Hennessey the wrong way from 12 yards to put his side a goal to the good.

Palace were less than impressed with the decision but could have been back on terms soon after when Cabaye connected well with a right-footed half-volley on the edge of the 18-yard box, forcing Gomes to dive to his right to push it behind.

Buoyed by that opportunity, the Eagles had the better of the game for a spell before the visitors had their next opportunity when Watson rolled the ball into the feet of Deeney. He worked a quick give and go with Odion Ighalo but fired well over from 20 yards.

Scott Dann was unable to get his head on a deep Wickham ball to the back post before Palace were fortunate to get away with a mistake when Deeney seized on a poor pass out of defence from Ward and immediately slipped in Ighalo. He produced his trademark scoop before trying to deceive Hennessey at his near post, but the keeper was able to block with his legs.

However, the home side were unable to clear their lines and when Behrami played the ball back in from the left side of the area, it eventually sat up for Amrabat. The Moroccan had a great chance to score but fired straight at Hennessey, although the referee adjudged Amrabat had handled to bring the ball under control.

Another fine chance came and went for the visitors in the last five minutes of the half when Watson clipped a free-kick forward, an unchallenged Deeney headed it on to an unmarked Ighalo on the right side of the area, but the Hornets’ top scorer got too much on it as he tried to lift it beyond Hennessey with his outstretched right leg.

Palace had been second best for a spell but in the last minute of the half they got back on terms – and there was a sense of inevitability about the scorer.

After the Hornets had initially repelled a long throw from the left, the ball was played back out to Wickham, he lifted a cross back into the heart of the 18-yard box and Adebayor got first run on his man to send a fine looping header over Gomes to make it 1-1 at the break.

Pardew made a change at the start of the second half, replacing Wickham with Lee, but there was little in the way of goalmouth action in the opening stages, although both sides were on the front foot.

But it was the hosts who had the first opening when some slack play allowed Zaha to feed the overlapping Souare on the left and he played a dangerous ball into the six-yard box which Prodl just managed to get to ahead of Jordon Mutch.

Moments later though, it took a superb save from Gomes to prevent the Eagles from taking the lead; the keeper displaying great reflexes to keep out an effort from Adebayor with his legs following some trickery on the left side of the area by Zaha.

Gomes was to be extended again when Cabaye let fly from 20 yards with his right foot, but again the keeper was equal to it, diving to his left to push the shot behind.

Flores decided to make his first change in the 63rd minute, bringing on Abdi for Amrabat after the January arrival had struggled to affect the game a great deal.

Another substitution followed eight minutes later as Suarez came on for Etienne Capoue but although the game had gone into something of a lull, Palace were continuing to ask more of the attacking questions.

Pardew upped the attacking ante by bringing on Fraizer Campbell for Mutch with 17 minutes of normal time remaining but moments later the Hornets should have been back in front.

It was no surprise that Deeney was again the instigator, receiving the ball on the right side of the area and sliding it along the line to Ighalo. He initially looked like he might pull the trigger but instead played it to his left where Nathan Ake was in plenty of space, but the left-back went for placement rather than power and fired straight at Hennessey.

Suarez then saw a shot charged down before he was booked for a foul on Ward at the other end and from the resultant free-kick on the right Lee tried to catch Gomes out at his near post with a dipping effort, but the keeper was able to shovel the ball away.

But with eight minutes remaining Watford got the chance they were looking for as Deeney capped a top-class showing with his second of the game.

It originated from a short Nyom throw on the right to Watson, they exchanged passes before the Hornets midfielder whipped in a cross from the right which glanced off a Palace defender’s head. But sensing something might happen for him, the Watford skipper had already pulled off into space at the far post and when the ball dropped for him, he took a touch before calmly firing past Hennessey to make it 2-1.

Palace were far from done though, and after Behrami’s fine challenge on Zaha had halted the Palace wide man’s dangerous run and conceded a corner, the set piece was repelled to the edge of the area where Cabaye connected with a superb left-footed half-volley which gave Gomes no change as it struck his right-hand post.

Having survived that let off, Watford were handed a further numerical advantage for the closing stages when, having over-run the ball as he took it out of defence, he launched into an awful two-footed challenge on Behrami that was reckless and Madley had no option but to show a straight red card.

Despite being reduced to ten men, Palace still almost snatched a draw at the death when Zaha was allowed to get in a cross from the left and Ward found space in the header, but sent his header over the top.

Crystal Palace: Hennessey; Ward, Dann, Delaney, Souare; Zaha, Jedinak, Cabaye, Mutch (Campbell 73); Wickham (Lee 46), Adebayor. Not used: Speroni, Mariappa, Chamakh, Kelly, Boateng.

Watford: Gomes; Nyom, Prodl, Cathcart, Ake; Behrami, Watson, Capoue (Suarez 71); Amrabat (Abdi 63), Deeney; Ighalo. Not used: Pantilimon, Paredes, Guedioura, Anya, Holebas.

Bookings: Suarez for a foul on Ward (76); Souare for a foul on Behrami – red card (90).

Attendance: 24,564 (2,541 away fans).

Referee: Bobby Madley.