Sigurdsson's stunner for Everton heaps the pressure on former Swansea pals
Everton's Gylfi Sigurdsson turned up the heat on former manager Paul Clement with a brilliant strike in a 3-1 victory to leave Swansea rooted to the bottom of the Premier League.
The Iceland international, who left the Swans in a £45m summer move, scored the vital second after Dominic Calvert-Lewin had cancelled out Leroy Fer's opener by converting Wayne Rooney's saved penalty on the stroke of half-time.
Rooney then made sure of the points with his sixth goal in five games when the hosts were controversially awarded a fortuitous second spot-kick in the 72nd minute.
It left Clement, who took over on January 3 with the club bottom of the table and guided them to safety, battling to save his job.
Just 12 points from 18 matches, and more worrying just 10 goals scored, leave the Welsh club four points from safety after just one win and four points from their last 10 matches.
The opposite is true for Everton, who are upwardly mobile under new manager Sam Allardyce with four wins and a draw from his first five matches in charge, earning 10 out of 12 points to lift his side from relegation contenders to a very credible ninth place.
A dreary opening half-hour, punctuated only by an unfortunate injury to Wilfried Bony less than four minutes in, was belatedly ended by Aaron Lennon screwing a shot wide.
Goodison awoke when referee Jon Moss booked Mason Holgate for a foul on Nathan Dyer despite there appearing to be no contact and only Jordan Pickford saving Tom Carroll's free-kick prevented more fury.
However, there was plenty of that aimed at Ashley Williams five minutes later when he lost Fer at a corner and the unmarked midfielder stabbed home.
Martin Olsson's low drive flew just wide as the visitors looked to capitalise on their advantage but it was soon wiped out when Roque Mesa tangled with Lennon.
Rooney's effort was tipped onto the post by Lukasz Fabianski but Calvert-Lewin converted the rebound.
The pivotal goal, in the 64th minute, could not have been a surprise for Swansea as former favourite Sigurdsson collected from Rooney and cut inside to brilliantly curl inside the far post.
Rooney blasted home his 10th of the season after Moss ruled Olsson's foul on Jonjoe Kenny was inside the area.