Arsenal boss Arsene Wenger admits that the Gunners are desperate to overcome Turkish giants Besiktas as they aim to secure a spot in the group stages of the Champions League.
"We are desperate to do it because we want to play in the Champions League and we know how big these games are,"the Frenchman told Arsenal.com.
The impact of an absence in Europe's top-tier insofar as finances and exposure does not need any more stressing, and Wenger further revealed that he is willing to do everything that he can selection-wise in order to qualify.
"We had to give a lot [against Crystal Palace], hopefully we will recover and be ready for Tuesday night," he added.
"We will assess Koscielny on Monday; if he's fit and capable to play, we play him. It was our plan to bring the Germans back in contention for Everton.
But in case of emergency I will take Mertesacker."
"But we have Bellerin, who was 19 today, who can come in. we are a bit short. I hope Koscielny responds well to today's game."