Barcelona said captain Iniesta would miss the match after he was not able to train with his team mates on Tuesday ahead of the encounter at the Santiago Bernabeu, where the Catalans will look to overturn a 3-1 deficit.
Iniesta, 33, was plagued by injury problems last season and rarely found top form. The midfielder joins Rafinha Alcantara and Thomas Vermaelen on the injury list at the Nou Camp.
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Barcelona did not give a recovery timescale for Iniesta, who may also miss the start of the league campaign on Sunday, when Barca host Real Betis.
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