Iniesta was replaced in the 72nd minute by Pedro Rodríguez.
He said that he was "surprised", but limited himself to saying that it was "the manager's decision".
"We had a massive desire to go through to the semi-finals, but our opponents are playing as well and want the same thing. They outplayed us in certain stages of the game and that won them the tie," he remarked.
"Being knocked out shouldn't affect us. It is a harsh blow because it is a wonderful competition where we had a chance to make it through to the semi-final, and hypothetically to the final.
"Now we have to treat the game against Granada as a final (for the league). There are not many games to go to try to win another league title, and we also have the Copa del Rey final. We'll be hurting today and tomorrow, but we'll fight for everything that is left."
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