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.”
Valverde says Barca struggled with the Reds’ high press and intensity, while the fourth goal from a quick Trent Alexander-Arnold corner caught them napping.
The head coach apologised to their fans in the post-match press conference and spoke of an understandably downbeat room.
“When you have a battle like tonight, you’re going to go through some really tough few days, like all our fans as well,” Valverde said.
“You’re going to suffer, the fans will suffer as well. That’s what it is like.
“You have to go through this penitence and we’ve not got long to go until the end of the league season.
“We’ve got the cup still to fight for and we’ve got to really finish the season well on a high after this.
“But at the moment we’re blown away, it’s terrible.”
Provided by Press Association Sport
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