Match ends, Watford 1, Swansea City 0.
Odion Ighalo's second-half strike earned 10-man Watford their first Premier League victory of the season at the expense of in-form Swansea.
The Nigeria forward pounced on a headed knockdown from Troy Deeney to fire in from eight yards and score the club's first goal at home this campaign.
Watford were reduced to 10 men when Valon Behrami was sent off after appearing to stamp on Andre Ayew.
Bafetimbi Gomis went closest for the Swans with a shot that was well saved.
So why did it fall in place for the Hornets?
It is a cliche, but belief appeared to be the key.
They reduced previously unbeaten Swansea to just eight efforts on goal - four of those off target.
Unsurprisingly, the visitors, who prefer to play a passing game as opposed to the Hornets' more direct approach, had the most possession with 61.8%.
But Swansea were second best in the duels, with Quique Sanchez Flores's men winning 54.8% of those battles in the second half.
This fighting spirit has been typical of Watford this season so far, having held Southampton, West Brom and Everton. The difference at Vicarage Road on Saturday was that they also managed to score.
What did the Watford forwards do right today?
The focus was on last season's hero Deeney, who scored 21 goals in total to help the Hornets to promotion.
He has yet to get off the mark this season, but played a major role in the goal and had support on Saturday from the scorer Ighalo.
The 26-year-old Nigeria international was impressive as a target man. He caused all sorts of trouble for Swansea's backline, with the usually unflappable Ashley Williams finding it difficult to handle his physical presence and pace.
His 84.6% success rate in distribution was the third best in his team and he won 50% of his duels.
Man of the match - Odion Ighalo (Watford)
Watford manager Quique Sanchez Flores:
"It was a really big experience to win first match in Premier League. It was a really tough match as Swansea is a good team.
"In the first half we played well and had control. It got complicated after the sending off.
"In the second half we had to defend a lot, I don't like to play like this. I'm really pleased and would like to dedicate this win to the fans."
Swansea manager Garry Monk:
"We got what we deserved. We just didn't perform. We couldn't get into it when the sending off came. We are very disappointed.
"We had a lack of focus on the things we do well. Our job is to come back and put those things right.
"We have no excuses. We were quite sluggish. I have no complaints with the result."
The stats you need to know
- Odion Ighalo has scored 18 goals in 23 league appearances in 2015 - more than any other player in the top four tiers this year.
- Iglaho's goal was the 100th Premier League goal scored at Vicarage Road - 3044 days after the 99th.
- Valon Behrami's red card was his first in 63 Premier League appearances.
- The Hornets secured their first Premier League win at Vicarage Road since April 2007 (4-2 v Portsmouth).
Watford, who have risen to 12th, face a trip to Newcastle next week, while Swansea, who fell to sixth, are at home to Everton.
- 22AbdiSubstituted forWatsonat 66'minutes
- 29CapoueBooked at 90mins
- 8BehramiBooked at 64mins
- 9DeeneySubstituted forDiamantiat 84'minutes
- 24IghaloSubstituted forBerghuisat 71'minutes
- 24CorkSubstituted forKi Sung-yuengat 66'minutesBooked at 67mins
- 10A Ayew
- 23G SigurdssonSubstituted forMacedo Lopesat 71'minutes
- 15RoutledgeSubstituted forMonteroat 60'minutes
- 4Ki Sung-yueng
- 17Macedo Lopes
- Robert Madley
- Shots on Target
Second Half ends, Watford 1, Swansea City 0.
Dangerous play by Eder (Swansea City).
Ikechi Anya (Watford) wins a free kick in the defensive half.
Attempt missed. Federico Fernández (Swansea City) header from the right side of the box is high and wide to the left. Assisted by Jefferson Montero with a cross.
Attempt missed. Jonjo Shelvey (Swansea City) right footed shot from outside the box misses to the left. Assisted by Bafétimbi Gomis.
Etienne Capoue (Watford) is shown the yellow card for a bad foul.
Lukasz Fabianski (Swansea City) wins a free kick in the defensive half.
Foul by Etienne Capoue (Watford).
Attempt saved. Steven Berghuis (Watford) left footed shot from the centre of the box is saved in the centre of the goal.
Attempt saved. Steven Berghuis (Watford) left footed shot from the centre of the box is saved in the centre of the goal. Assisted by Jurado.
Corner, Swansea City. Conceded by Jurado.
Offside, Swansea City. Neil Taylor tries a through ball, but Bafétimbi Gomis is caught offside.
Jonjo Shelvey (Swansea City) wins a free kick in the defensive half.
Foul by Etienne Capoue (Watford).
Attempt saved. Jonjo Shelvey (Swansea City) right footed shot from outside the box is saved in the centre of the goal.
Attempt missed. Jurado (Watford) right footed shot from outside the box misses to the left.
Foul by Neil Taylor (Swansea City).
Jurado (Watford) wins a free kick on the right wing.
Substitution, Watford. Alessandro Diamanti replaces Troy Deeney.