Arsenal 0 Chelsea 1 player ratings Diego Costa - 8 out of 10

The striker was the centre of headlines the last time these two sides met in the season and he proved so again today. It was his run forwards that forced Mertesacker into his last-ditch tackle, for which he was sent off for, before Costa helped create and then finish off Chelsea's opening goal. Costa was impressive considering he hardly trained this week following his bruised tibia against Everton but he paid for it when he came off with an injury in the second period.

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