Barcelona manager Hansi Flick labelled his team's humbling 4-0 defeat by Atletico Madrid in the Copa del Rey semi-final first leg as a "wake-up call" and urged his side to learn from the chastening experience.
At a raucous Metropolitano Stadium, Atletico handed the defending champions their heaviest loss of the season, leaving Barcelona a mountain to climb in the return leg at Camp Nou.
Flick, candid in his post-match assessment, bemoaned his team's lack of cohesion but remained defiant about their prospects in the second leg.
"Look, we didn't play well as a team. And when you don't play like that, you don't play well. There was a long distance between players. There was a lack of pressing," Flick told reporters.
"Sometimes it's good to learn a lesson like that. Today was a wake-up call, a tough defeat. We have to accept this lesson."
The German coach admitted his side were second-best from the opening whistle, though he saw some improvement after halftime.
"We didn't play well from the first minute. We have a young team, but that's no excuse. The second half was better... But we'll fight. We have two 45-minute halves to score two goals in each half," Flick said.
While Flick addressed his team's shortcomings, Atletico boss Diego Simeone was full of praise for both his players and the electric atmosphere at the Metropolitano, which he said spurred them to a standout performance.
"You could feel incredible energy in the stadium, and life is energy," Simeone said.
"It was directed from our fans towards us, and we were able to match it... I think we played very well. Today's match will be remembered regardless of how the tie ends.
"Our fans need these matches, these important nights. We were able to repay their enthusiasm in the best possible way."
The second leg takes place in a fortnight, with Barcelona left clinging to Flick's resolve and Atletico inspired by their commanding lead.