Swansea City threw two precious points away at the Liberty Stadium after Watford's Danny Graham cancelled out a great opening goal from Stephen Dobbie.
Swans boss Brendan Rodgers made two changes to the side that lost 1-0 at Scunthorpe on Saturday.
Stephen Dobbie came in for Leon Britton in the attacking central midfield role alongside Joe Allen and Mark Gower, while Luke Moore replaced Craig Beattie up front.
The changes saw the Swans line up with the same side that impressed so much in the 3-0 victory over Leeds United at the Liberty 10 days ago.
Watford had no fresh injuries going into tonight's game. Lloyd Doyley, Danny Drinkwater and Michael Bryan were still out for the Hornets, but they welcomed back captain John Eustace from suspension.
Eustace replaced Andy Weimann and Dale Bennett came in for Adam Thompson.
Manager Malky Mackay said: "Brendan has a good team and you saw that last week when they turned over Leeds handsomely, who are also a top team.
"We know the size of the task but it is one that we will meet head on."
Swans:Dorus de Vries, Angel Rangel, Alan Tate (c), Ashley Williams, Neil Taylor, Joe Allen, Mark Gower, Stephen Dobbie, Scott Sinclair, Luke Moore, Nathan Dyer. Subs:Yves Ma-Kalambay, Darren Pratley, Albert Serran, Cedric van der Gun, Craig Beattie, Jazz Richards, Leon Britton.
Watford: Scott Loach, Lee Hodson, John Eustace (c), Martin Taylor, Adrain Mariappa, Don Cowie, Troy Deeney, Danny Graham, Will Buckley, Ross Jenkins, Dale Bennett. Subs: Rene Gilmartin, Marvin Sordell, Andy Weimann, Piero Mingoia, Matty Wichelow, Adam Thompson, Chez Isaac.
Ref: L Mason
Swansea made a lively start as Watford were forced to clear two early corners. And it took less than five minutes for the referee to show the first yellow card when Dale Bennett brought Scott Sinclair crashing to the ground.
It was a surprisingly open game early on as Troy Deeney tried his luck from the edge of the area which Dorus de Vries got down save easily.
Swansea were happy to keep the game open and flowing as Joe Allen sent Nathan Dyer through, but Scott Loach was down well to save at the expense of a corner. Mark Gower delivered it and Angel Rangel hit a fierce shot goalward only for Loach to pull off a fine save with eight minutes gone.
The home side kept the pressure up and Dobbie tried his luck from the edge of the area which skipper John Eustace managed to deflect over the bar.
Watford, despite a little bit of time-wasting, were prepared to have a go and when Danny Graham got in behind Ashley Williams in the 20th minute, he shot wide when the league's top scorer had time to take it on.
Swansea came back immediately and it took another fine save from Loach to deny a fierce effort from Dyer.
The deadlock was finally broken in the 27th minute when a lovely ball from Gower split the Watford defence and Stephen Dobbie tucked a cool finish into the far corner for his sixth of the season.
Swansea remained on the front foot, but were given a scare in the 34th minute when Will Buckley was given too much room inside the area to force a good save from de Vries at the near post as the midfielder cut back from the by-line.
Sinclair curled an effort wide two minutes before the interval, before de Vries was forced to come to Swansea's rescue on the stroke of half-time when Graham looked yards offside. But the Dutch 'keeper did well again at his near post.
Half-time: Swans 1 Watford 0
There were no changes for the second-half as Dobbie tested Loach within two minutes with a 25-yard effort which the 'keeper did well to tip over.
The neat inter-play between Allen, Luke Moore and Dobbie set up Dyer who fired just over from the edge of the area with 51 minutes on the clock.
Watford made their first change in the 59th minute when Marvin Sordell replaced Buckley.
Swansea had taken their foot off the gas a bit when Troy Deeney was given a free header from a corner. Fortunately de Vries was well placed to gather under his crossbar.
But just as Watford were starting to get themselves back in the game, the Swans enjoyed a 10-minute spell of possession that took the sting out of the Hornets.
It was a second goal that Swansea needed though to make their possession count and kill off the game.
Instead it was Watford who grabbed the all-important goal when Deeney's ball caught out Alan Tate inside the area and Danny Graham fired home an easy chance with 78 minutes gone.
Swansea continued to see plenty of ball without testing Loach in goal.
Ashley Williams saw yellow for a clumsy tackle on Eustace before Craig Beattie replaced Moore with five minutes remaining.
Tate almost won it for Swansea in injury-time with a curling shot which crept the wrong side of the post.
But it was two points lost in the end after all the possession Swansea enjoyed.