Neymar checked in field and floated a measured chip towards the chaos, at which point time seemed to slow down.

A battered, terrified Paris Saint-Germain defence pushed out, or some of them did. Barcelona's attackers, joined by goalkeeper Marc-Andre ter Stegen, bustled about searching for room.

Sergi Roberto found some and flung out a leg as the ball dropped towards him. Surely, they couldn't.

They did. Pandemonium.

From the wreckage of a 4-0 first-leg humiliation, Barcelona had won 6-1 at a delirious Camp Nou and reached the quarter-finals of the 2016-17 Champions League.

"It's a negative experience for me and for the club. We need to learn from it," said shellshocked PSG boss Unai Emery on an evening that overwise lacked for understatement.

He would get the chance to put those lessons into practice with a shiny new toy.

The €222million man

"This is the best game I've ever played," Neymar told beIN SPORTS afterwards. "This can only happen once in a lifetime."

Roberto might have scored the goal for the ages, but Neymar was unquestionably the man of the hour for Barcelona. He was majestic and unplayable, especially in those closing moments.

As the clock ticked into the 88th minute, it was 3-1 and PSG appeared to have staggered through the storm. Then the Brazil superstar whipped a free-kick from the left into the net, converted a dubious Luis Suarez-won penalty and crafted the decisive goal.

It was one of the rare, glorious moments in his Barcelona career where Lionel Messi found himself as a member of the supporting cast. Apparently, that feeling appealed to Neymar. Maybe he could have more of it.

As Messi and Suarez have shown more recently, there can be numerous reasons for generational talents to decide their best interests are served away from a deeply dysfunctional Barca.

When PSG audaciously decided the best way to avoid similar embarrassment in future was to sign the architect of their own downfall, Neymar's conflicting motivations will have been plentiful. But the allure of moving out of Messi's shadow when his €222million clause was activated served as a stirring factor.

The gauche execution of the transfer coup means Neymar has often been a figure of ridicule during his time in Paris. His performances have generally been excellent.

Across 103 games for the capital club in all competitions, he has 83 goals and 42 assists. His minutes-per-goal ratio of 105.5 is the sixth best in Europe's top five leagues since his world-record move, behind Erling Haaland, Robert Lewandowski, Sergio Aguero, Cristiano Ronaldo and Messi.

In the overall scoring charts during this period Neymar is 16th, with exactly half of Lewandowski's astounding 166. The Bayern Munich striker has also played 68 more games than Neymar, underlining the regularity with which the 29-year-old has been forced to grapple with injury.

He will miss his Camp Nou return due to a groin problem, just as he missed showpiece last-16 encounters against Real Madrid in 2018 and Manchester United in 2019. Both times PSG were eliminated.

The 'Remontada' complex

If Barcelona believed their feat of logic-defying escapology was something to weave into their Mes que un club mythology then the subsequent years have disabused them of that notion.

In the very next round, the 4-0 loss in Paris was almost matched in Turin, where Juventus were 3-0 winners.

Gianluigi Buffon, Leonardo Bonucci, Georgio Chiellini, and the rest were never going to be as obliging as Emery's men and locked down a 0-0 draw to progress. Even more frustratingly for Barca, the Bianconeri lost that season's final to Real Madrid.

Earlier in the campaign, during the group stages, Barcelona were beaten 3-1 at Manchester City despite Messi giving them the lead. A pattern had started to emerge of chronic vulnerability against opponents of comparable quality.

Madrid also wrestled LaLiga from their bitter rivals' grasp in 2016-17, heralding the end of Luis Enrique's tenure. Ernesto Valverde came in, sifted through the wreckage of the Neymar saga with impeccable dignity and delivered back-to-back league titles.

Europe continued to spin spectacularly out of Barcelona's control, however, as they swallowed bitter repeat doses of their own "Remontada" medicine.

A 4-1 first-leg advantage in the 2018 quarter-final against Roma dissolved as a 3-0 defeat in the Italian capital saw them dumped out on away goals.

Liverpool were beaten 3-0 in the first leg of the 2019 semi-final, only to roar back and pulverise Barca 4-0 at Anfield.

That result didn't do for Valverde, but a Supercopa de Espana semi-final loss to Atletico Madid midway through last season did. The Blaugrana's jitters in continental knockout matches has seeped into their domestic business - see Athletic Bilbao's success in this season's Supercopa and last week's Copa del Rey semi-final first leg defeat to Sevilla.

All that is small beer compared with the multi-directional catastro-shambles that was a doomed Quique Setien leading Barcelona to an 8-2 Champions League quarter-final mauling at the hands of Bayern Munich.

Eight. Two.

The scars of defeat and decline

Emery survived the Camp Nou collapse and also added Kylian Mbappe to his squad, meaning there was no danger of Monaco repeating their spectacular 2016-17 Ligue 1 success.

But a meek, Neymar-less defeat to Madrid meant regaining domestic supremacy did not stop PSG from moving him on in favour of Thomas Tuchel.

The former Borussia Dortmund boss hammered collective responsibility into a lavishly assembled but unbalanced squad, although their next big European night suggested a club still haunted.

An authoritative 2-0 win at Manchester United pointed a simple path to the quarter-finals in 2019, only for them to stumble to a 3-1 loss on home soil, knocked out on away goals.

With Neymar in harness, they plotted a path to the rearranged 2020 final in Lisbon, coming back to beat Tuchel's ex-employers over two legs before scraping past Atalanta and defeating RB Leipzig.

There was no shame in losing 1-0 to a magnificent Bayern, but PSG's path to the final still leaves them aching for a major scalp in the final stages of the Champions League.

Now under Mauricio Pochettino, a beaten finalist with Tottenham in that glorious 2018-19 edition, it can be debated whether this Barcelona still rank as one.

In his pre-match news conference, head coach Ronald Koeman stated: "That's what we like to show, that we can compete with the best teams in Europe." It is hard to imagine a similar clarification being needed during any other stage of the Messi era.

The era PSG hoped would wash away their night of Catalan shame, that of Neymar, splutters on with their talisman booted to the sidelines once more. A Barcelona on the brink of financial ruin are only beginning to reckon with the sizable cracks Roberto's goal did so much to help paper over.

When these two wounded giants face off on Tuesday, back at the scene of that historic heist, they would be forgiven for shuddering at the sight of one another.