Hansi Flick conceded Barcelona got schooled by Atletico Madrid, but vowed his team will give their all to fight back in their Copa del Rey semi-final.

Barca went down 4-0 on Thursday, putting Atletico in complete control of the two-legged tie.

Eric Garcia, who scored an early own goal, compounded Barca's misery by receiving a red card in the second half, although by then the damage had already been done.

Antoine Griezmann, Ademola Lookman and Julian Alvarez were on target for Atletico, and the holders would have to stage an extraordinary comeback to reach the final.

While Flick has not given up hope, he acknowledged Atletico were by far and away the better team.

"We didn't play very well in the first half as a team," Flick said, as reported by ESPN.

"We had too much distance between everyone. We didn't press how we wanted.

"In the first 45 minutes or more, we got a lesson. Sometimes it's good in the right moment. Maybe today was the right moment.

"I am still proud of my team, maybe not today in the first 45 minutes, but across the whole season. When you see how many injuries we have all season, how we adapt...Today was a heavy loss but I am proud of my team.

"We will come back. We need to start from the beginning [of games]. When you see Atlético players, they had more will, more hunger. And this is what I want from the first minute. We didn't show that in the first half.

"We have the second leg. We will fight for that. If we are able to win each half 2-0, this is our goal. We need our fans in Camp Nou and we will see what happens."

Barca found themselves having conceded four goals in the first half of a game for just the second time in the past 21 years. The previous occasion came in their 8-2 loss to Bayern Munich in the Champions League in 2020.

Garcia, meanwhile, became the first Barca player to score an own goal and be sent off in the same match since at least the start of the 2004-05 season.