By Chris Harris at Stamford Bridge
Our hopes of closing the gap on the league leaders were scuppered by a ruthless Chelsea side at Stamford Bridge.
Marco Alonso climbed above Hector Bellerin - clattering him in the process - to nod in the opener after Diego Costa’s header had thumped against the crossbar.
Gabriel, on for the dazed Bellerin, had our best chance of an equaliser with a header that Thibault Courtois brilliantly tipped over.
We looked capable of clawing our way back into the match but Eden Hazard ran from the halfway line to score a fine individual goal.
Danny Welbeck went close but Cesc Fabregas added a late third after an error from Petr Cech, before Olivier Giroud headed an even later consolation.
Chelsea are now 12 points ahead of us. It’s a long way back from that.
Arsene Wenger made three changes to the side for this London derby.
Bellerin was back at right back, Theo Walcott returned on the right flank and Alex Oxlade-Chamberlain replaced the injured Aaron Ramsey.
Gabriel and Giroud dropped to the bench alongside Welbeck, but Lucas was missing with a minor injury.
If we wanted encouragement ahead of a daunting task, September’s 3-0 dismantling of Chelsea was the place to look. But the Blues have been relentless since then, winning 13 games straight to open up a nine-point lead at the top.
Our last league double over Chelsea came in the 2003/04 title season. Another double was required to keep this season’s title hopes alive.
We started promisingly, Mesut Ozil seizing on a defensive lapse and finding Alex Iwobi for a shot that was deflected wide.
But Chelsea moved through the gears and were always a threat from crosses. Gary Cahill’s downward header from Pedro’s cross served as a warning, and another right-wing cross undid us.
This time Costa beat Bellerin to the ball to thunder a header off the bar via the fingertips of Cech. The ball flew up in the air and Alonso had enough of a run-up to get above Bellerin and nod in the rebound.
In doing so he injured the Spaniard and Bellerin couldn’t continue. Was it a foul? The referee thought not. On came Gabriel.
Costa fired into the side-netting as the league leaders look to turn the screw, and for a while he and Hazard looked capable of taking the game away from us.
But we found a second wind as the first half drew to a close. Ozil found Oxlade-Chamberlain on the edge of the box and he dinked the ball over the Chelsea defence for Gabriel to power in a header that Courtois tipped over.
Ozil had space for a shot in first-half stoppage time but Courtois saved Chelsea once again.
The final stages of the first half gave us hope for the second, but Hazard made the task all but insurmountable.
There didn’t seem to be clear and present danger when the Belgian collected the ball on the halfway line, but he built up a head of steam to shrug off Coquelin and wrong-foot Laurent Koscielny before beating Cech.
Wenger brought on Giroud and Welbeck to change things up. Iwobi dropped into midfield alongside Oxlade-Chamberlain. That left us more vulnerable to the counter-attack, but we had to push on.
Welbeck looked lively, and his stooping header from Shkodran Mustafi’s cross tested Courtois, who just got down to push the ball past his post.
Mustafi himself powered a header wide from the resulting corner, but that was as close as we came to getting a foothold in the match.
Fabregas - a former Arsenal captain - capitalised on a rare miskick from Cech to lob in a third. He didn't celebrate.
Giroud nodded Nacho Monreal’s cross past Courtois as the game ticked into stoppage time, but by then it was no more than a consolation.
Referee: Martin Atkinson
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