The Gunners are in dire straits heading into their final group game, and essentially face a straight shootout with the Greek giants for a place in the Last 16.
Dire early results look like costing Arsenal, who will definitely drop out of Europe’s elite competition if they fail to beat Olympiakos away.
Even a victory might not be enough, with the Athens heavyweights having won 3-2 at the Emirates Stadium, and the Gunners must better that scoreline to advance.
As he looks to secure the required result, Wenger has made a surprise inclusion to his starting XI, drafting Walcott back into his side despite the England forward only just making his comeback from a month on the sidelines.
Walcott is part of an attacking unit containing Mesut Ozil, Joel Campbell and Olivier Giroud.
— CaughtOffside (@caughtoffside) December 9, 2015
Wenger has resisted the temptation to include Calum Chambers as a central midfielder, instead employing Mathieu Flamini and Aaron Ramsey in the middle of the park.
A first-choice defence of Hector Bellerin, Per Mertesacker, Laurent Koscielny, Nacho Monreal and Petr Cech will be charged with keeping the Greeks at bay.
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