BLAST: Mike Dean sends off Gabriel

Costa was fortunate to avoid a red card for swinging an arm at Laurent Koscielny just before half-time before being booked for a confrontation with Gabriel in the aftermath.

Dean dismissed Gabriel seconds later after the centre-back appeared to flick his foot out at Costa as the duo continued to have words with each other near the half-way line.

Arsenal were reduced to nine men 12 minutes before full time when Santi Cazorla was given a second yellow card for a mistimed challenge on Cesc Fabregas.

Goals from Kurt Zouma and Eden Hazard in the second-half sealed victory for Chelsea but Wenger directed his wrath at Dean.

"I would not like to be Mike Dean tonight," Wenger said.

"Costa twice should be sent off. He hits him in the face in purpose. In every game he has aggravation and he gets away with it because of the weakness of the referee. We knew before the game he is only looking at that.

"Gabriel should not have responded at all but the two sending offs for us and Costa staying on the pitch is a shame."