Borussia Dortmund captain Emre Can railed against his team's "soft" performance after they were routed 4-0 by Barcelona in the first leg of their Champions League quarter-final tie.

Dortmund need a miraculous comeback to have any chance of replicating last season's run to the competition's final, after a chastening outing at Montjuic.

Robert Lewandowski struck twice against his former club and was joined on the scoresheet by wingers Raphinha and Lamine Yamal.

Lewandowski now has more goals against Dortmund, who he left for Bayern Munich in 2014, than he does against any other team in his career, with 29 in 28 matches.

For Dortmund, it was their joint-heaviest defeat in any European Cup/Champions League match (also 4-0 to Ajax in 2021-22) and another low in a miserable season.

Can was visibly frustrated after the match and told DAZN that it was a matter of attitude, rather than tactics or coaching decisions, that led to the defeat.

"It's not a question of system but rather of whether everyone is willing to give 100% and make the sacrifices required in games like this," Can said.

"Too many things went wrong in the game, we didn't play well today. We were soft. We weren't cohesive enough. And on top of that, we made simple mistakes.

"At this level, those types of mistakes are punished harshly. That's why we went down here today.

"We were playing against a great Barcelona team, they obviously have several good players, definitely, so the only way you can beat them is if you go out there as a team, something we didn't do.

"I think we could have done much better, even though they're so good, I know that. You have to go for it and we didn't, to be honest.

"Now we need to put in a good performance and try to win the next game. We owe it to our fans, and we need to give it everything we've got."

Barca will be full of confidence for Tuesday's return leg, with Dortmund eighth in the Bundesliga on 41 points, five adrift of the Champions League qualification places.

Hansi Flick's Blaugrana could still end the season with four trophies. Having won the Supercopa de Espana, they lead LaLiga and will face Real Madrid in the Copa del Rey final this month.