Pat Nevin
BBC Radio 5 live

"What a shame, really. Chelsea have been getting more and more into this game and the attitudes of both sets of players had been excellent, with really good work-rates and energy.

"Then right at the end the dynamic of this game has changed. We might now not get as good second half. We will pour over that sending off - did Gabriel deserve his red card? Let's be clear, Costa is no angel."

I'm looking forward to reading the description of that red card on the Chelsea website...

Pat Nevin
BBC Radio 5 live

Image source, PA

"Wenger almost tried to dummy his way out of the handshake with Mourinho before the start, but was just a little too late!"

Phil McNulty
BBC Sport chief football writer

Bizarre end to the half with Gabriel sent off at the conclusion of a lengthy spat with Diego Costa. Arsenal might say, with a lot of justification, that Costa started all that with three straight hands into the face of Arsenal defender Laurent Koscielny - surely he should be off as well?

Um, it feels a bit lame to be talking about a pre-match handshake after that load of handbags, but coming up is a picture of the moment the managers met...

Gabriel's dismissal was Arsenal's 78th Premier League red card, and their fifth v Chelsea. Only Everton (79) have more.  

Paul Humphreys:  Only got himself to blame Gabriel. You've both got yellows just leave it! Terrible discipline   

Michael Lee:  Cue Mourinho saying everyone picks on Costa..  

Richard Thiardt:  Love or hate it. Mission accomplished Diego.  

Pat Nevin
BBC Radio 5 live

"They both had received a yellow card, but Costa was still getting at Gabriel. He walked backwards into Costa, and the referee must deem he walked back and tried to stamp on Costa. 

"They were both trying to wind each other up and in the end the battle was won by Costa, because Gabriel was wound up just that little bit more. And the referee was in a brilliant position."

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At least this half is ending with a bang, but the replays I've seen of that red card show that Gabriel stuck out a leg as Diego Costa walked into him. That is very harsh if that is the case. I'm sure it will all be cleared up soon enough. 

I was right, this is not over. Mike Dean signals that Gabriel kicked out at Costa in the aftermath of that initial incident, and that is a red card. Gabriel is not going quietly either.

That ended with a yellow card apiece for Diego Costa and Gabriel, but it is not over yet... Costa is not letting this lie - he claims Gabriel just stood on his toe.

Postpublished at 44 min

44 min

Chelsea 0-0 Arsenal

Referee Mike Dean has got a lot to sort out here. Chelsea striker Diego Costa is in the thick of it, clashing with Laurent Koscielny and then Gabriel, who arrived late to get involved.

Here come Chelsea again, and Petr Cech has to push away Pedro's snap-shot from the edge of the area.

All of a sudden this game is end-to-end, with Branislav Ivanovic having a shot blocked on the edge of the Arsenal area before Arsenal break to threaten through Aaron Ramsey.

Pat Nevin
BBC Radio 5 live

"I thought Chelsea might have started this season with Cahill and Zouma together in the centre of defence. Zouma hadn't made any mistakes, and he is the future for Chelsea, so perhaps the quicker they make that selectorial change the better. 

"It would have surprised me if Terry had started today, considering the pace of Arsenal.

Femi John Atoyebi:  Hazard wrestled to the ground. How is that not a penalty to Chelsea

Steven Kabuoro:  A clear push on Hazard right infront of the refs eyes.  

David Robinson:  Never ever a penalty. Correct call. Gabriel stood his ground which he has every right to do & Hazard didn't have the strength  

We have not had too many shots today, which is probably why Kurt Zouma decides to have a pop from 40 yards out. He gets plenty of power behind his effort, but it is well over.