Bafetimbi Gomis's goal completed a three-minute turn around for Swansea

Sanchez scores sixth goal in his last four league games

Arsenal lose their second league match this season

Gylfi Sigurdsson scores his second goal of the campaign

Swansea have claimed 13 points from 18 at home

Swansea came from behind with two late goals to claim a memorable win over Arsenal at the Liberty Stadium.

Arsenal took the lead when Alexis Sanchez finished from close range after an excellent run and pass from Danny Welbeck.

But a stunning Gylfi Sigurdsson free-kick and a fine header from substitute Bafetimbi Gomis sealed Swansea's victory.

The win sees Garry Monk's men leapfrog the Gunners into fifth place in the Premier League table.

For Arsene Wenger's side, meanwhile, defeat caps a miserable week after their Champions League collapse against Anderlecht on Tuesday, in which they threw away a three-goal lead to draw 3-3.

MOTD2 analysis Martin Keown on Arsenal: "Arsenal's downfall was that they were not ready when they lost the ball. You have to prepare for the worst, otherwise you are not going to be ready when you lose possession. That is something you don't have to train at, it is a mindset you go on to the pitch with, and you have to have players who take responsibility at key times." Read more: 'Arsenal pay for criminal defending'

There were some nervy moments from the Gunners' defenders, with Calum Chambers surviving a Swansea penalty appeal after appearing to shove Wilfried Bony to the ground inside the area.

Clear scoring opportunities were at a premium in the first half as two slick but congested midfields cancelled each other out.

Arsenal threw away game - Wenger

Arsenal did not manage a shot on target until a minute before half time, as Welbeck combined well with Sanchez before his effort was palmed away by former Gunner Lukasz Fabianski.

Arsenal's flashes of danger before the break were a sign of things to come, as they made the stronger start to the second half.

Alex Oxlade-Chamberlain wasted an excellent opportunity when his shot was saved by Fabianski, but the Gunners were ruthless with their next effort.

The visitors latched on to a poor pass from Bony and launched a counter-attack, from which Welbeck sped into the box, turned past Ashley Williams and squared the ball for Sanchez, who fired in from six yards.

Swansea were fantastic - Monk

Arsenal seemed in control at this point but, within 15 minutes, the match was completely transformed.

Swansea were awarded a free-kick 25 yards from goal after Kieran Gibbs was booked for fouling the hosts' debutant Modou Barrow.

Sigurdsson then compounded Gibbs' punishment as he curled an unstoppable shot into the top corner.

Arsenal barely had time to register the blow of Sigurdsson's leveller by the time Swansea took the lead less than three minutes later.

Montero, who had given Chambers a torrid afternoon on Swansea's left wing, floated in an inviting cross for Gomis, who nodded the ball beyond a static Szczesny and into the bottom corner.

Arsenal tried to salvage a point with some desperate long balls late on, but Swansea withstood the pressure to claim a first win in six games against the Gunners.

Swansea manager Garry Monk: "It's about belief. We talked about belief before the game, about how good we have been and how good we can be. We showed our character.

"They got the goal. I thought it was an even game, we made the changes and thankfully they went for us today.

"Gylfi Sigurdsson has been disappointed previously that he has not had many opportunities to produce what he did today but what a great goal and that put us in the ascendency.

"We beat Manchester United on the first day, we have just beaten Arsenal but we take each game as it comes. We are doing a lot of work on the training ground and at the moment it is paying off."

Arsenal manager Arsene Wenger: "It's disappointing to throw a game away like we did. We were 1-0 up and had to be tight defensively and wait for that second chance. But you have to credit Swansea who didn't give up.

"In football you can believe anything is possible, any minute you can concede. Bafetimbi Gomis is good in the air and it can happen. You have to accept that Swansea will fight until the last minute. We eased off at 1-0 and let them back into the game.

"Football is down to performances. We are here to produce performances, and didn't do that right until the end of the game."

Line-ups

Match Stats Line-ups Swansea 1 Fabianski

22 Rangel

27 Bartley

6 Williams Booked at 50mins

3 Taylor Booked at 37mins

4 Ki Sung-yueng Booked at 41mins

14 Carroll Booked at 63mins Substituted for Britton at 87' minutes

11 Emnes Substituted for Barrow at 67' minutes Booked at 90mins

23 G Sigurdsson

20 Montero

10 Bony Substituted for Gomis at 76' minutes Substitutes 2 Amat

7 Britton

18 Gomis

19 Tiendalli

25 Tremmel

56 Fulton

58 Barrow Arsenal 1 Szczesny

21 Chambers Booked at 62mins Substituted for Sanogo at 90' minutes

4 Mertesacker Booked at 55mins

18 Monreal

3 Gibbs Booked at 74mins

16 Ramsey Booked at 45mins Substituted for Walcott at 79' minutes

20 Flamini Substituted for Wilshere at 79' minutes

15 Oxlade-Chamberlain

17 Sánchez Booked at 86mins

19 Cazorla

23 Welbeck Substitutes 7 Rosicky

9 Podolski

10 Wilshere

14 Walcott

22 Sanogo

26 Martinez

39 Bellerin Referee : Phil Dowd Attendance : 20,812 Match Stats

Former Arsenal goalkeeper Lukasz Fabianski had little to do for much of the first half

Danny Welbeck registered Arsenal's first shot on target after 44 minutes

Former Arsenal goalkeeper Lukasz Fabianski had little to do for much of the first half

Arsenal forward Santi Cazorla was caught a number of times by the Swansea defence

Gylfi Sigurdsson has been involved in nine goals this season - two goals and seven assists