Bilbao stunned Barca at San Mames 1-0.
"We had the game under control, but the goal really hurt us. San Mamés is always a tough place to come to," said Iniesta.
"Defeats always happen for a reason, but I don't think we can compare this one with the game against Ajax. We had some good phases of play tonight, but we have to be more efficient.
“We put in a good first half and we played well at times after the break, but the goal really shook us and although we really tried, we couldn't come back.”
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