The Gunners face the unenviable task of overturning a 2-0 first-leg deficit at Camp Nou after Lionel Messi’s brace secured victory for Barcelona at The Emirates last month.
Arsenal have failed to win a game since their loss to Barca, falling further off the pace in the Premier League title race and exiting the FA Cup.
Walcott turned 27 on Wednesday ahead of Arsenal’s vital Champions League second leg against the holders in Cataluna.
And France defender Koscielny remembered to send wishes Walcott’s way despite the prospect of a huge game against Barcelona on the horizon.
— Koscielny (@6_LKOSCIELNY) March 16, 2016
The Gunners are bidding to reach the quarter-finals for the first time since 2010.
They reached the knockout stage for the 16th season running thanks to a 3-0 win at Olympiacos FC on 9 December. They had lost three of their first four group games but finished as group runners-up thanks to a superior head-to-head record against Olympiacos.
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