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

Andy Martin:, external Winners: Chelsea. Surprise: Ludogorets. Flop: Liverpool.

Andrew Priestley:, external Winners: Real Madrid. Surprise: Juventus. Flop: Liverpool.

Ankur Goyal:, external Winners: Barcelona. Surprise: Arsenal. Flop: Bayern Munich.

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

Image source, Getty Images

Nothing is ever easy - just ask Celtic.

The Scottish Premier League champions were dumped out of Europe last night by Slovenian side Maribor, after a humiliating 1-0 home loss.

Imagine the reaction from the Emirates if similar happened tonight? It is safe to say Wenger would be feeling the heat once more.

So, the nine-year trophy drought is finally over at Arsenal.

You could almost sense those dark clouds lifting from the Emirates when the Gunners beat Hull to lift the FA Cup in May. The Community Shield followed earlier this month and four points from the opening two Premier League games leaves all happy in north London.

It doesn't take long for that to change though. Defeat tonight and the mood would quickly darken again around the Emirates.

The teams are out.

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Image source, Getty Images

Anyone banking on Alexis Sanchez to be prolific in Europe for Arsenal should perhaps think again. The former Barcelona man has only scored three Champions League in 24 appearances. Abou Diaby has scored more....... Having said that Besiktas's squad only have six goals in the competition between them.

Image source, @MesutOzil1088

Arsenal midfielder Mesut Ozil:, external We have to make it for the 17th participation in the Champions League - no matter how!

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

"It's a big night for Arsenal football club. In the past we have taken it for granted that they would slide through these qualification games.

"But this Turkish team will not travel particularly well. I hoping this is when Alexis Sanchez really announces himself to the Arsenal fans. He is an outstanding talent, full of pace. He's not the biggest player, but he can cause problems on the deck."

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

Image source, AP

Something has to give then. Both Besiktas and Arsenal have been fairly formidable in Champions League qualifying matches but that can't go on for both of them this evening.

Crystal Palace co-chairman Steve Parish has spoken to BBC Radio 5 live following the appointment of Neil Warnock as his new manager. Malky Mackay or Tim Sherwood had been favourites to get the job earlier in the week before talks broke down.

He said: "There was no lack of candidates. We made the choice of Neil because he is the best person to take us forward now. He did a great job when he was here before and he understands the club.

"He offered his services very early on so it was always an option that was there. The picture you try to paint that he was the last choice is not true. The standard of people that applied was very high... World Cup winners.

"Everybody that we saw and we enquired about wanted very much to manage the football club. I'm sure if we had rung them last night they would still have wanted to manage the club."

Image source, AFP

What do we know about Besiktas? Former Chelsea and Newcastle striker Demba Ba will be leading the attack for the Turks, having scored a treble in the previous round.

The Turks are managed by ex-West Ham man Slaven Bilic. The Croat will missing from the Turks' dugout after being sent to the stands for arguing with referee Milorad Mazic in the first leg.

"It's not ideal of course. I regret it and would love to be down there with the boys," he said. "But I don't see a huge problem in it. We have prepared our game plan and I have a big belief in my assistants and they'll do the job there."

Arsenal midfielder Aaron Ramsey:, external Good luck tonight guys, finish the job off!

Image source, Reuters

Summer signing from Barcelona Alexis Sanchez will be the man asked to operate as the lone striker in the absence of Olivier Giroud, although he did little to help his cause against Everton at the weekend,

He was replaced at half-time at Goodison following an ineffective 45 minutes as the focal point of Arsenal's attack, but Wenger is convinced he can operate as more than a winger.

He said: "You do not convict a player on one half. It was not all bad what he did, there was some quality in what he did. It was just that on the day we needed more physical presence."

Phil McNulty
BBC Sport Chief Football Writer at Emirates Stadium

"Thousands of Besiktas fans have travelled to Emirates Stadium in the hope of making the Champions League group stage after a goalless first leg in Turkey - and have travelled very noisily if the wall of noise outside the stadium 90 minutes before kick off was anything to go by.

"Arsenal manager Arsene Wenger realises how precariously this qualifying tie is balanced and his job has been made even harder by the absence of suspended Aaron Ramsey, sent off in the first leg, and injured striker Olivier Giroud."

Arsenal: Szczesny, Debuchy, Mertesacker, Koscielny, Monreal, Wilshere, Ox, Flamini, Cazorla, Ozil, Sanchez. Subs: Martinez, Chambers, Coquelin, Rosicky, Podolski, Campbell, Sanogo

Besiktas: Zengin, Koybasi, Franco, Gulum, Motta, Hutchinson, Ozyakup, Kavlak, Pektemek, Sahan, Ba Subs: Gonen, Kurtulus, Sivok, Tore, Uysal, Koyunlu, Tosun

As Arsenal and Besiktas battle to clinch their own place in the Champions League group stages, we want to know your tips in the competition this season. Let us know who you expect to win it, a surprise contender and a big team you expect to flop. I'll start you off...

Winners: Real Madrid. Surprise: Arsenal. Flop: Barcelona.

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

Arsenal striker Lukas Podolski:, external Winning is a habit! Come on Gunners.

Image source, PA

The omens are good for Arsene Wenger with Arsenal having never shipped a goal at home to Turkish opponents. Before this tie, Arsenal had never faced Besiktas.

Image source, @arsenalfc

Arsenal FC:, external The boss has arrived at Emirates Stadium ahead of tonight's Arsenal v Beskitas game.

Stoke: Butland; Wilkinson, Shawcross (c), Huth, Muniesa, Cameron, Adam, Odemwingie, Walters, Moses; Crouch. Subs: Sorensen, Arnautovic, Wilson, Diouf, Sidwell, Teixeira, Shenton.

Portsmouth: Jones; Webster, Devera, Whatmough, Butler, Ertl (c), Awford; Holmes, Wallace, Barcham, Taylor. Subs: Brezovan, Robinson, Close, Atangana, Hollands, Storey, Westcarr

Arsenal manager Arsene Wenger: "Alexis Sanchez is sharp in his movement, he is quick. I believe he can give them trouble. Yaya Sanogo is ready as well. It was a tight decision but Sanchez is used to playing under pressure.

"Laurent Koscielny has important experience, Calum Chambers has done well but maybe he needs a breather. I have told the players to keep calm and trust in the way we play."