The Gunners take on Diego Simeones men on Thursday night at the Emirates, with the competition their last remaining hope of silverware and a route back into the Champions League.
However, despite the importance of the match, The Mirror report that Wenger will not return No.1 goalkeeper Petr Cech to the starting XI despite the veteran returning to full fitness.
Cech missed Sundays thumping 4-1 victory over West Ham with a hip injury but is back in training and most of the squad had assumed he would be between the sticks against Atletico.
But Wenger has ignored his players and surprised them by choosing to stand by Ospina, who is considered the cup goalkeeper and played in eight of their Europa League matches so far.
Wengers decision is something of a gamble given Ospinas rather inconsistent showings in the past, especially with Arsenals entire season – and Wengers legacy – hinging on the Europa League.
Mesut Ozil was not in the matchday squad against West Ham last time out, the first game Arsenal had played since Wenger announced he would leave the club, but the German is back and ready to take on Atletico.
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