Diego Costa Tweets dressing room picture after helping Chelsea beat Arsenal

Striker was again the centre of attention at Stamford Bridge

(Instagram/Diego Costa)

A smiling Diego Costa Tweeted a picture from the dressing room after helping Chelsea beat Arsenal at Stamford Bridge.

The striker was again the centre of the action after provoking Arsenal centre-back Gabriel Paulista into a reaction that eventually got him sent off - after clashing with Laurent Koscienly, Costa and Paulista went at each other before the Brazilian defender was shown red for kicking out.

However, Arsenal manager Arsene Wenger believes referee Mike Dean got the decision wrong, arguing that Costa should have been sent off twice.

After the match Costa posted a picture that said: "Great win today, Thanks for the support!"

Wenger, however, made it clear he was not impressed with Costa's antics.

"(There is a) big sense of injustice," Wenger told BT Sport 1. "I think Diego Costa is a red card.

"I wouldn't like to be Mike Dean tonight because I cannot understand the situations. Twice he (Costa) should have been sent off.

"Look at the situation well before the cross comes in, he hits him (Laurent Koscielny) in the face on purpose.

"He makes a fuss of it. In every game there is aggravation but he gets away with it because of the weakness of the referee.

"We are guilty because we gave in on that and responded to it. We knew before the game that he was only looking for that and when he touches him he goes down like he has been killed."

In response, Chelsea boss Jose Mourinho said: "The game is about all different aspects. The technical, emotional, physical and with a combination of these factors normally the best team wins. We were the best team. We were dominant, we were in control.

"I played my first derby as manager in September 2000 and I remember my words to my players. To win the derby - emotional control. I always repeat the same words before derbies.

"For me it was a fantastic performance (from Costa). He played the game like the game has to be played. He's fast, he's aggressive and he's good to recover the ball and offers us different qualities."