Arsenal 0 Chelsea 1

Ten-man Arsenal failed to regain top spot in the table after stretching their winless run against Chelsea to nine Premier League games.

The Gunners had skipper Per Mertesacker sent off for bringing down Diego Costa, who promptly fired the only goal of the game five minutes later to earn his side the points.

It was Arsenal’s first home league defeat since the opening day of the campaign and kept them in third place, three points behind leaders Leicester.

There were early opportunities at both ends, with Joel Campbell trying to wrap his left foot around Theo Walcott’s cross but miscuing it before Laurent Koscielny’s sloppy pass presented Oscar with the chance to test Petr Cech.

Willian might have put Chelsea ahead when Nemanja Matic’s cross sat up for him to volley and his first attempt thudded back off Mertesacker, with the rebound clasped by Cech.

But the decisive moment came in the 18th minute when Walcott’s ball was charged down and Willian led the counter-attack, threading a pass through for Costa and leaving Mertesacker exposed.

The floundering Arsenal captain chopped Costa down, prompting referee Mark Clattenburg no alternative but to show the red card – and Arsene Wenger sacrificed Olivier Giroud to bring on Gabriel and restore his back four.

That decision was unpopular with the home crowd – and it became even more so when Costa stole in to slam Branislav Ivanovic’s cross past Cech with the defence still readjusting.

Although Walcott was unlucky to be caught offside a couple of times, Arsenal were hindered by the lack of anything resembling a striker and it was Costa who came closest to adding a second goal, forcing another save from Cech.

An equaliser never looked likely until the very last kick of the first half, when Aaron Ramsey’s piercing ball picked out Mathieu Flamini, but the Frenchman steered his volley over the bar.

Wenger bowed to the inevitable with half an hour remaining, sending on Alexis Sanchez for his first appearance in almost two months – yet inexplicably not to operate as a centre-forward.

The closest Arsenal’s 10 men got to a sniff of goal was when Thibaut Courtois palmed Mesut Ozil’s free-kick onto his own defender’s back and the ball rolled loose, with nobody able to force it into the net.

For the Blues, who remain unbeaten since Guus Hiddink’s return, Cesc Fabregas might have rubbed extra salt into his old club’s wounds with a couple of opportunities that were easily fielded by Cech.

The Arsenal goalkeeper charged forward for an injury-time corner but, despite the potential for a fairytale equaliser, it was his former team-mates who were celebrating at the final whistle.

Arsenal: Cech; Bellerin, Mertesacker, Koscielny, Monreal; Ramsey, Flamini; Campbell (Sanchez 57), Ozil, Walcott (Oxlade-Chamberlain 75); Giroud (Gabriel 20).

Chelsea: Courtois; Ivanovic, Zouma, Terry, Azpilicueta; Mikel, Matic; Willian, Fabregas, Oscar (Hazard 78); Costa (Remy 68).