Match ends, Swansea City 3, Cardiff City 0.
Jamie Paterson inspired Swansea City to a thumping victory in the south Wales derby to pile the pressure on Cardiff City boss Mick McCarthy.
Paterson put Swansea ahead with one of the most memorable goals in the recent history of this fixture, flashing home a shot from 25 yards.
He then laid on goals for Joel Piroe and Jake Bidwell to secure Russell Martin's biggest result as Swans boss.
But it is now six straight defeats for the ailing Bluebirds.
The latest reverse - and the nature of it - is only likely to add to speculation about McCarthy's future at Cardiff, who are just three points clear of the Championship relegation zone in 20th.
Swansea climb to 17th courtesy of only a third league win since Martin took charge in early August.
His side remain a work in progress, but this was the strongest indication yet that they are on the up after a difficult start to the season.
Cardiff did not start the game like a team in such miserable form, although they were fortunate not to concede a third-minute penalty after Curtis Nelson's clumsy challenge on Ethan Laird.
Swansea struggled to get their passing game going in the early stages, and Cardiff should have gone ahead when Ryan Giles latched on to Kieffer Moore's through ball only for Ben Hamer to save a tame shot.
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Moore then broke the offside trap but fired straight at Hamer before Swansea dragged themselves into the contest in spectacular fashion.
There was a lovely touch and pass by Ryan Manning, who fed Paterson to centre for Piroe, whose point-blank shot was saved at the near post by Alex Smithies.
But the danger was not gone. Swansea kept possession and eventually worked the ball back to Paterson, who took a touch before unleashing a fierce, curling drive which hit both posts before bouncing over the line.
It was a moment of inspiration from Paterson, the kind Martin's Swansea needed having struggled for goals this season.
Cardiff have not scored a first-half goal in the Championship all campaign, and there was little sign of that miserable record changing as Swansea grew in confidence having gone ahead.
McCarthy needed a response after the break, and there were early set-piece opportunities as Aden Flint's shot deflected over and Nelson headed off target from the resulting corner.
But there were Swansea threats too, with Laird and Ryan Bennett drawing saves from Smithies before Martin's team conjured a stylish second goal.
Piroe laid the ball off to Paterson, then ghosted into space to accept a clever return pass.
The Dutchman's finish was clinical, as he took the ball down on his chest and rolled home his seventh goal of the season with his weaker right foot.
On a day of racing pulses, Piroe's contribution was ice cool.
Swansea appealed again for a penalty as Mark McGuinness slid in on Korey Smith, then held their heads in frustration as Smith headed wastefully wide with the goal at his mercy.
Another golden chance came and went as Olivier Ntcham's shot was saved, but Swansea's third eventually came thanks to more fine work from Paterson.
Fed by Laird, the former Bristol City player - signed as a free agent on the eve of the season - chipped the ball to the far post for Bidwell to head home from a yard.
Swansea head coach Russell Martin:
"It was an incredible performance. I'm really proud of the players, the courage they showed on an occasion like this.
"I feel like a performance like that has been coming.
"We spoke before the game about weathering the storm early on whilst Cardiff have intensity, energy and aggression.
"After that first 15 minutes I thought we controlled the match in a good way. The connection is building all the time and the way we hurt Cardiff in the second half was excellent."
Cardiff City manager Mick McCarthy:
"I am bitterly disappointed. It was the same at Blackburn when we had our chances. We had two great chances today and we have got to be better in both boxes, that's for sure. The [first] goal we concede - just giving the ball away we did was disappointing.
"They are a good footballing team and once they go 1-0 in front we have got to go and chase it and got opened up. I am really disappointed in the end.
"I always expect them to give everything, which they do. It's difficult when you are on a run like we are, all of a sudden it doesn't look cohesive and sometimes you get opened up.
"The game-plan worked well at the start, but once we conceded it was disappointing from there on. They give everything they have got, the players, but I would just like us to be better of course."
- 2BennettSubstituted forCabangoat 81'minutes
- 3ManningBooked at 63mins
- 7SmithSubstituted forNtchamat 67'minutes
- 17PiroeSubstituted forCullenat 85'minutes
- 30BrownSubstituted forColwillat 80'minutes
- 7BacunaBooked at 26minsSubstituted forCollinsat 68'minutes
- 8RallsSubstituted forVaulksat 84'minutesBooked at 90mins
- 29M Harris
- James Linington
- Shots on Target
Second Half ends, Swansea City 3, Cardiff City 0.
Jamie Paterson (Swansea City) wins a free kick in the defensive half.
Foul by Sean Morrison (Cardiff City).
Matt Grimes (Swansea City) wins a free kick in the attacking half.
Foul by Kieffer Moore (Cardiff City).
Will Vaulks (Cardiff City) is shown the yellow card for a bad foul.
Ethan Laird (Swansea City) wins a free kick on the right wing.
Foul by Will Vaulks (Cardiff City).
Corner, Swansea City. Conceded by Aden Flint.
Offside, Cardiff City. Sean Morrison tries a through ball, but James Collins is caught offside.
Substitution, Swansea City. Liam Cullen replaces Joël Piroe.
Substitution, Cardiff City. Will Vaulks replaces Joe Ralls.
Offside, Swansea City. Olivier Ntcham tries a through ball, but Ethan Laird is caught offside.
Corner, Swansea City. Conceded by Aden Flint.
Attempt blocked. Ethan Laird (Swansea City) right footed shot from the right side of the box is blocked. Assisted by Kyle Naughton.
Substitution, Swansea City. Ben Cabango replaces Ryan Bennett.
Substitution, Cardiff City. Rubin Colwill replaces Ciaron Brown.
Attempt missed. James Collins (Cardiff City) header from the centre of the box is close, but misses to the left. Assisted by Ryan Giles with a cross.
Goal! Swansea City 3, Cardiff City 0. Jake Bidwell (Swansea City) header from very close range to the top left corner. Assisted by Jamie Paterson.