Shell-shocked head coach Ernesto Valverde admits Barcelona were "rolled over" and "blown away" by Liverpool in an extraordinary semi-final.
Only four times in Champions League history has a side overturned a first-leg deficit of three goals or more to progress from a knockout tie.
Barca were on the wrong end of one of those spectacular comebacks at Roma last year and tasted another shock defeat at Anfield on Tuesday.
Divock Origi goals either side of a brace from substitute Georginio Wijnaldum sealed Liverpool a memorable 4-0 win, putting them through to the Madrid final 4-3 on aggregate as Barcelona were left reeling.
"It's happened again," head coach Valverde said. "It happened last year.
"It's true that it has been different games, the first leg and second leg.
"They started really well, and they pinned us back. Early goal, we reacted well after that.
"We managed to control things a little bit in the second half of the first half. We had half chances to score.
"I think that we conceded two goals and then they really kind of got on top of us after those two quick concessions.
"We haven't managed to get on the scoresheet tonight. They scored two in two and they kind of us rolled us over, really.
"They have been really strong, they played really well. We've got to congratulate them on the performance they put up in the tie as a whole.
"It is a terrible result for our fans and for ourselves. We didn't expect a situation like this. This is what has happened to us.
"It is really, really unfortunate but credit is due to Liverpool."