The scale of the defeat, following an earlier admission from Carlos Corberán that a loss at Deportivo had been a "disgrace," left the head coach facing further scrutiny, even as fans directed much of their anger at the club's directors and owners rather than the dugout.
"Today I'm analysing a game against a rival that was superior to us from start to finish. Conceding a goal so early made everything an uphill battle," Corberán said. "The chances we had after that goal, in quick transitions, we didn't take, and it would have been important to do so.
"And our rival found the formula to sink us. After the third goal it was difficult to turn it around."
Asked whether he had the strength to lift the team out of its current situation, Corberán said the squad remained united despite the pain of the result.
"It's a situation that leaves us all bruised, but it doesn't leave us broken either. It's a difficult situation, but we're going to look for solutions as a team, with honesty and hard work," he said. "It's a moment where we accept any criticism of us, because the fans start the season with great excitement and as a coach I haven't managed to give them that excitement or that level."
Pressed on whether he had considered resigning, Corberán insisted his resolve remained intact.
"I always have strength and conviction since I took this job. I have the responsibility to turn around a situation that started more complicated than last year. But with conviction and hard work we have to turn it around," he said.
Hansi Flick, by contrast, was delighted with a dominant display.
"It was fantastic, we dominated the game from the start. We controlled and dominated. That's what I want to see," the Barcelona head coach said.
Flick played down individual contributions, pointing instead to the collective quality on show.
"For me the important thing is the three points, but we have quality on the pitch. We can attack well against low blocks, especially in this heat," he said.
Flick also gave an update on Lamine Yamal's fitness following his recent knock.
"Yesterday he trained and had no problems. This morning we spoke and he told me he could play, that he was fine," he said.
The Barcelona boss also praised the impact of players returning from the bench, singling out Dani Olmo's recent contributions.
"I'm very happy with Olmo's minutes, he always wants more. And that he does it coming on from the bench and making the best decisions for the team," Flick said.