Arsenal 0 Swansea City 1

Former Arsenal goalkeeper Lukasz Fabianski thwarted his old club with a string of saves to dent their chances of snatching the runners-up spot.

Fabianski, making his first return to Emirates Stadium since he left to join Swansea last summer, proved a point – and helped to earn three for his new side as he repelled everything the Gunners could throw at him.

And a late header from substitute Bafetimbi Gomis sentenced Arsenal to defeat for the second time this season as they stayed three points behind Manchester City, albeit with a game in hand.

Arsenal’s best opportunity to break the first-half stalemate came as early as the third minute, when Olivier Giroud met Aaron Ramsey’s cross with a glancing header onto the roof of the net.

Otherwise, the Gunners’ efforts to puncture Swansea’s back line met with failure – sometimes of their own making, typified when Per Mertesacker mistimed his run and blocked Mesut Ozil’s free-kick.

Operating without a recognised striker, the visitors crammed the midfield and set out to hit Arsenal on the counter-attack with the speed of Nathan Dyer and Jefferson Montero.

However, they did not create a great deal, although David Ospina was called into action to make relatively routine stops from Angel Rangel and Jonjo Shelvey.

The Gunners stepped up the pace towards the end of the first period, but they were still unable to find a way through despite Giroud’s shot on the turn, which did not curl enough to trouble Fabianski.

Swansea looked the more dangerous side straight after the break, with Ki Sung-Yueng’s effort deflecting behind and Ospina then reacting swiftly to dive on Shelvey’s cross as the Korean prepared to pounce.

Yet the Gunners responded with a good spell of pressure and Fabianski denied Giroud and Santi Cazorla, while Ramsey turned Neil Taylor inside out before drilling his shot into the side netting.

With the scoresheet still blank, Arsene Wenger ordered Jack Wilshere and Theo Walcott into action – and the latter almost made an immediate impact, stabbing Hector Bellerin’s deflected cross goalwards.

But Fabianski stopped the ball on the line – and the keeper was also equal to the task to foil both Nacho Monreal and Cazorla, followed by a double stop from Sanchez and Walcott.

And Swansea applied a sucker punch five minutes from time as Montero swung over a cross for Gomis, who outjumped Monreal for a header that crossed the line despite the efforts of Ospina.

The home side pressed forward frantically during the closing stages but, despite chances for Sanchez and Mertesacker, nothing could prevent their first home league reverse since November.

Arsenal: Ospina; Bellerin, Mertesacker, Koscielny, Monreal; Cazorla, Coquelin (Wilshere 67); Ramsey, Ozil, Sanchez; Giroud (Walcott 69).