The Gunners head into the game with the unenviable task of having to overturn a 2-0 first-leg deficit following their loss at Emirates Stadium last month.
Arsenal have been struggling to find consistent form in recent weeks and have won just one of their last seven outings in all competitions.
And their opponents on Wednesday looked to be totally relaxed as Barcelona trained ahead of Wednesday’s game.
Here are some of the best pictures from Tuesday morning’s Barcelona training session.
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