Celtic players don't try to hide from how they feel about their night to forget in Barcelona

This was understandable because it was almost as if Lionel Messi and his better than average supporting cast came from another world.

This Celtic team might not have the likes of a Henrik Larsson, Stiliyan Petrov or Shunsuke Nakamura, who belonged in the Champions League, but they are good players, excellent professionals who have won big games, played international football and have pride bursting out of every pore.

Read more: Patrick Roberts was "embarrassed" as brilliant Barcelona ran rings around Celtic

It was a hard night and one which will not be shrugged off easily.

Captain Scott Brown described the 7-0 defeat at the hands of Barcelona as “unacceptable” as he reflected on a nightmare second half which ended with the club's record defeat in a European match.

Read more: Scott Sinclair was left battered, bruised and bewildered after Celtic's football lesson by Barcelona

“I think if you look back on the first half, we’ve defended really well,” said Brown, who was one of the few to get pass marks.

“They scored a very early goal – a great finish by Messi – but we almost managed to get ourselves back into the game, we missed a penalty and Scott Sinclair had a goal disallowed for off-side.

“But second half we let ourselves down and five goals in 45 minutes is not good enough for anyone. To come here, and I know they’re a great team who will always create chances and score goals, we need to be better as a team.

"We need to defend better, from the front all the way back.

“I do think it’s unacceptable. We’ve been here before and got beat 2-1, 1-0 and there’s also been a 6-1. But the way we played, it’s not our best performance and we’ve let ourselves down.

"I think the main thing is we watch the video back and see how we can be better as a team, defending and everything else. We also have to be a lot better on the ball.

“We’ve definitely gone from a high to a low in just two or three days. It’s not acceptable. We’ve sat down and talked about it in the changing room.

"But, we need to deal with that now, we need to kick on and get a result at Inverness. Then we’ve got Manchester City in a couple of weeks.”

The Celtic supporters situated in the top tier of the Nou Camp and those watching through their fingers at home have been reluctant to criticise their team too much given the world-class abilities of their opposition.

Brown, however, still believed the Scottish champions should never concede seven goals no matter how difficult the situation.

“I know Barcelona are a great team and they’re going to press you. They are always going to create and score goals,” he said.

"But, we can’t just write a result like this off because of how good Barcelona are. We’re in a hard group and if we think like that already then we’re not going to score any goals or win any games.

“We need to start thinking and focus a lot better during the games and work harder as a team on and off the park.”

Brown hinted that harsh words were spoken at half time, saying: “What happens in the dressing room stays in the dressing room. That’s all I'm saying.”

He also pledged that Celtic would recover and get better as he looked ahead to the remaining five Group C games in the Champions League.

“I definitely think there will be a reaction against Manchester City when we play them at home next,” Brown said.

"We need to show that, and we know that at Celtic Park anything can happen. We’ve let ourselves down and need to respond strongly.

“We’ve beaten Barcelona and AC Milan before there, so here’s hoping we can focus on that and try to get three points as quickly as possible.

“I’ve never lost a game by seven. It was bad enough losing 6-1 here. But 7-0 beats anything else I’ve ever had. No one wants that kind of defeat. It’s a hard game to have happened and we should be doing better than that.”

Celtic can only lick their wounds and hope it was not one of those defeats which can affect a squad for a couple of weeks.

Read more: Patrick Roberts was "embarrassed" as brilliant Barcelona ran rings around Celtic

Brown said: “Here’s hoping this is the worst result for Inverness because we now need to bounce back as quickly as possible. We need to keep our 100 per cent record in the league.

“We’ve been doing really well in the league and that’s always our priority. But we also want to try to do as well as we possibly can in the Champions League.

“We know we’re a lot better than what we showed against Barcelona. We let ourselves down majorly. We know that as a team. But now it’s about bouncing back as quickly as possible.”

Mikael Lustig was another who while acknowledging the greatness of Barcelona, felt that losing seven goals was something no Celtic team should do.

He said: "Barcelona are a great side, they can do that to anyone, but that is no consolation. It is about pride. I am not sure what to say if I’m being honest.

"I don’t think I’ve ever lost 7-0 before. Of course, you can say we faced the best attacking players in the world, but to let in five goals in the second half wasn’t good.

“It was tough to be out there. This is football. We played really well on Saturday but that now feels far away.

"It is a long season, we have a really good team and we have made a good start, but right now we are a bit sad and have to think about what we can do better.

“We did face a really good team but 7-0 is too much.”