Las Palmas stunned Barca 2-1 on Saturday.
Torres later said: "We are disappointed, frustrated, angry... We have not been effective and we have not played well, that is the reality. But we know what kind of team we are and we have to think about the next game.
"We had a spectacular start, we've had some bad games, but it's not a bad dynamic, it's just a one-off. We're capable of turning it around, we've done it before. It's time to reset and clear our minds.
"In the second half, with the tie, we were going up, but their second goal just killed us and then we barely played, they wasted time. In the end, we accumulated people in the area, but today it wasn't possible."
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