So calamitous was PSG's Champions League exit to Barcelona, that they are in danger of becoming a joke

The French champions capitulated from the 85th minute onwards

Barcelona completed one of the greatest comebacks of all time at the Nou Camp (Getty)

Some on the Paris Saint-Germain side readily admitted it. In their dressing room, there were tears.

That’s completely understandable, even if so much of this scarcely believable game was not. One of the most relevant reasons for this sensational Barcelona comeback was that the French champions just psychologically collapsed. There is one stat from that that is almost as stunning as the game. PSG completed just four passes between the 85th minute and the final whistle, and three of those were from kick-offs after conceding the decisive goals. They fell apart.

One of the most relevant outcomes of that, though, is what it will do to the team and maybe the club.

This was supposed to be a transformative night for PSG, and it might well prove so, just not in the way they could have ever imagined. Far from finally taking the next step against one of Europe’s super clubs, they regressed, failing to reach the quarter-finals for the first time since 2012. That, however, is a mere trivial detail in what could end up a deeply traumatic night. “It’s difficult to cope with,” Thiago Silva said.

It is not just that they were knocked out, or even that Barca completed the comeback so talked about before the game. It was that they recovered from the initial onslaught and actually scored the goal that should have put them in the last eight. Instead, it only heightened the feeling of utter failure, because it made the collapse all the more pronounced and exquisite. It was a humiliation.

It also makes this one of those results that leaves a stain on a club that is almost impossible to live down, in the same way that Atletico Madrid’s last-minute defeat in the 2014 Champions League final became so newly emblematic of their old neuroses as a club. PSG could now have an even greater neurosis about this competition. Far from announcing themselves as part of the European elite, they ensured that their very name will now always be associated with being on the calamitous side of amazing comebacks. It was that bad, and they face the danger of becoming that bad a joke.

Already so obsessed with winning the Champions League, PSG now desperately have to win it to cleanse themselves of this horror show; to give themselves the kind of memory that actually trumps this.

They have never looked further away, and that will make it all the more traumatic, because they had thought themselves so close. Now, more introspection is required. They have to think about what they do differently.

They will probably do what most clubs do in such situations, mind: sack the manager, even if at the end of the season.

Unai Emery was oddly calm and composed after the game, not looking in any way devastated in the manner you might expect, but that might be because he has already accepted his fate. He was also quite gracious. Although Emery pointedly mentioned how “refereeing decisions went against us”, it wasn’t like he was using it as an excuse.

Then again, how can you excuse that? Even if the Barcelona penalties were as dubious as those here, you can’t really complain about that when the most basic instruction before the game - a Champions League knock-out no less - is ‘just don’t lose by five’.

“We lost everything in the closing minutes,” Emery admitted.

Emery is likely to lose his job in the summer after crashing out of Europe (Getty)

If it now seems certain that he will lose his job, it’s tough not to wonder what this will do for some of the players. This should have been the night that Edinson Cavani banished so many complaints about how many big chances he missed, given that he scored what should been the big goal to make it 3-1, only to then squander a much easier chance at 3-2.

You’d wonder how Angel Di Maria would have reacted to that. A former Real Madrid player, he made a shushing gesture to the crowd when Cavani scored.

There was only disquiet when he was through on goal at 4-1, but the Argentine missed in a way arguably worse than Cavani. He could have killed the game, but only did further damage to his reputation.

That, however, was just one of many moments when PSG players lost their heads and thereby their composure. The tone and pattern was set so early in the game with that first Luis Suarez goal, given that it came about largely because of the utter panic in their box as much as the Barca striker’s hunger. It did not bode well, and they continued to make so many nervous mistakes.

“We didn't play today,” Silva admitted, having had a personal nightmare. "We were on the pitch, but we didn't do anything we prepared."

They could barely say anything either.

"Those five minutes, I can't find an explanation,” Marco Verratti stated of how the game ended, a grand finale for Barcelona and everyone else, a very public execution for this club, their players and probably their manager.

“It's a negative experience for me and for the club,” Emery said with considerable understatement. “We need to learn from it.”

They need to do much more than that. And first, they just need to recover from it. That is likely going to take a long time, as those tears illustrate.