Arsenal were unfortunate to go behind when Chelsea scored on the break after Ramires had fouled Francis Coquelin, whilst the same player then fell over his own feet to win a penalty for the second goal.

"The referee gave a lot of free-kicks and some for much less than the Coquelin one," he said.

"It's frustrating. It doesn't mean we should have conceded the goal but in the big games these decisions have big implications. It wasn't a penalty, and he could have given Ramires a yellow card [for diving] as well. But we didn't make enough of our corners, free-kicks and the chances we created. That's why we lost the game. It's very damaging for our position in the league and difficult to swallow."