Wenger’s thinking will be two-fold. First and foremost, he will want Mertesacker fresh for what, in theory, should be an even more difficult away fixture at Everton on Saturday. He clearly also already has huge faith in Chambers and Wenger has always been one of the biggest risk-takers in football. Yes, there is the possibility tonight of his gamble backfiring but, in his mind, he will also be thinking about the opportunity and experience that Chambers will gain by playing in such a pressurised match. That could be invaluable later in the season if Mertesacker or Koscielny are unavailable at a crucial moment. Wenger will also reason that, even if things do not go to plan in Istanbul, the situation will surely still be recoverable at the Emirates next Wednesday.