Ouch. Mathieu Debuchy doesn't mind a challenge does he? This time there is no blame as he and Ramon Motta only have eyes for the ball and collide with each other. Good commitment and a quick wipe down with the magic sponge and both are back on their feet.

A sublime diagonal pass from Santi Cazorla sets Mesut Ozil down the left. The German skips past one defender but, with just Alexis Sanchez ahead of him, his forward pass is to no one and again Arsenal's promising move breaks down.

We want to know your tips in the Champions League this season: winners, surprise and flop.

Batmanu Eboue:, external Winners: Arsenal. Surprise: Liverpool. Flop: Chelsea.

Ashley Williams:, external Winners: Barcelona. Surprise: Dortmund. Flop: had to be Celtic already.

And defending Liverpool against those who say they will be the flops....

Oli Dent:, external Surely the fact that Liverpool have reached the UCL groups for the first time in so many seasons means they have already not flopped.

Let us know your thoughts via #bbcfootball, text 81111 (UK users only) or post on the BBC Sport Facebook page.

Alexis Sanchez takes the free-kick from 20 yards but it is easy for Tolga Zengin as he grabs the ball comfortably in his midriff.

Veli Kavlak is cautioned for protesting against a free-kick awarded on Santi Cazorla. Chance here...

Past the 20-minute mark and Besiktas are warming to their task. Arsenal aren't getting a lot of time on the ball as the Turks chase and hustle everything.

A Mathieu Debuchy cross from the right causes a moment of panic in the visitors' box but a poor pass from Alexis Sanchez allows Besiktas to clear.

Ex-Arsenal defender Martin Keown
BBC Radio 5 live at Emirates Stadium

"It's interesting when Olcay Sahan is in possession because Besiktas seem to target Nacho Monreal. They have played two or three diagonal balls out to the right-hand side. They see him a weakness I think.

"Monreal has not played too much European football."

Image source, AFP

Arsenal are well on top but Besiktas, as expected, are digging in and looking to frustrate. Not sure Olcay Sahan will be too happy though after being pole-axed by Mathieu Debuhcy. A deserved booking for the Arsenal man.

At the other end Demba Ba almost breaks clear but goalkeeper Wojciech Szczesny just about gets there.

Phil McNulty
BBC Sport Chief Football Writer at Emirates Stadium

"Arsenal manager Arsene Wenger is fired up in his technical area. In constant dialogue with the fourth official - not always with justification."

Image source, AFP

The first goal of the night comes at the Britannia as Jon Walters gets the final touch to a Marc Muniesa free-kick to steer the ball home.

Martin Keown
BBC Sport

"Oxlade-Chamberlain on this right-hand side is a good match up with Ramon Motta. Plenty of pace there.

"You get the feeling that Oxlade-Chamberlain is trying a bit too hard. He needs to believe in himself a little bit more. He has great pace and ability but sometimes you need to be a bit more confident in your ability."

Listen to BBC Radio 5 live for live commentary on Arsenal v Besiktas.

Another good chance for the Gunners. Goalkeeper Tolga Zengin looks unsure with the ball at his feet in the penalty area and can only clear straight to Santi Cazorla. The Spaniard attempts to chip the stranded keeper from 30 yards but gets it horribly wrong and his shot goes well wide.

A couple of early chances for Arsenal.

Ex-Arsenal defender Martin Keown
BBC Radio 5 live at Emirates Stadium

"Jack Wilshere takes it to right hand side of the goal and then puts it wide. You are waiting for the net to bulge there really. That's Wilshere at his best, running through from midfield. It just needed a bit more quality at the end of it."

A free-kick in a good position for Arsenal. Santi Cazorla whips the ball in from the left but it is too easy for goalkeeper Tolga Zengin.

Arsenal should be ahead though as Jack Wilshere races through on goal, after an advantage is played following a shove on Alexis Sanchez, but the midfielder rolls the ball wide. He should score.

Image source, Getty Images

Sho:, external Hopefully Alexis Sanchez gets off the mark tonight. Think he only needs one goal to fully kick off his Arsenal career.

Luke Campbell:, external Arsenal have made the Champions League stages 17 years in a row. If there's a man to stop that run, it's Demba Ba!

Ogombe Maxwel:, external It would be better if Arsenal don't qualify for the Champions League group stage, their team is much better suited for the Europa League.

For the moment though, Arsenal are camped in the Turks' half. An Alex Oxlade-Chamberlain corner is flicked on by Per Mertesecker but the ball rolls to safety.

Home player Mesut Ozil is getting jeered by the Besiktas fans, presumably for opting to play for Germany over Turkey - show them your World Cup winners medal Mesut!

Besiktas can expect to do a lot of defending tonight but they have already shown in the early stages they can can break with pace. Arsenal will have to be careful.

Neat turn from Jack Wilshere before setting Alex Oxlade-Chamberlain down the right. The England international beats his man very easily but his low cross is cleared. Bright start from the Gunners.

Phil McNulty
BBC Sport Chief Football Writer at Emirates Stadium

"Great atmosphere inside Emirates Stadium. It seems Alex Oxlade-Chamberlain is now such an established Arsenal figure that he is allowed to simply be announced as "The Ox" when the teams are read out. Big cheer for Lukas Podolski, whose future at Arsenal has been in some doubt."

Money, reputation and supporters goodwill.

It is all at stake at the Emirates tonight. Game on.