BARCELONA, Spain — Lionel Messi sprinted straight past the goal. He ran away from Paris St.-Germain’s players, who lay stricken on the turf. As his Barcelona teammates raced after Sergi Roberto, an improbable hero on an impossible night, Messi peeled off toward the fans.
When he reached the edge of the field, he leapt on top of an advertising board and held his arms aloft, raised to the gods. He paused there, perched precariously, for a few seconds, and then he fell into the heaving, delirious mass of worshipers who awaited him. The crowd, senseless and mostly shirtless, seemed to swallow him whole.
Behind him, Barcelona’s bench was emptying, a great torrent of players and coaches and medical staff running onto the field, running in circles, running in ecstasy and exhilaration, running to burn off the adrenaline coursing through their veins after the most remarkable comeback the Champions League — soccer, in fact — might ever have seen.
Above him, all around him, the towering stands of Camp Nou seemed to liquefy. A crowd of 96,000 danced and waved the senyera, the flag of Catalunya, Barcelona’s unofficial emblem, giving thanks for the miracle. This stadium, this faded, beautiful ruin, shook for 20 minutes after the final whistle on Wednesday, as the players bounced on the field, looking for all the world as if they had won the competition, rather than just one round, or one match, even if it was by the score of 6-1. The building shook, and the rest of Europe shook, too.
Three weeks before, Barcelona was out of the Champions League — beaten, 4-0, in Paris, humiliated and exposed. No team in the competition’s history had ever recovered from such a yawning deficit.
A few days later, Luis Enrique, Barcelona’s manager, confirmed that he would depart at the end of the season, saying the job had “exhausted” him. The task awaiting his successor, all of a sudden, seemed a mammoth one.
This Barcelona team has dominated European soccer’s consciousness for the past decade. It has won the Champions League four times — 2006, 2009, 2011 and 2015 — and has been virtually ever-present in the semifinals of the competition for the last seven years.
It is, though, an aging squad. A handful of its stalwarts have departed — Xavi Hernandez, Carles Puyol — and more still are reaching the autumn of their careers. Messi, Luis Suárez and Sergio Busquets are all nearing 30; Andres Iniesta and Gerard Pique are beyond it.
The days when Barcelona passed its opponents to death have long gone, too, abolished by Enrique in favor of a more direct approach designed to get the best out of the so-called M.S.N. strike force: Messi, Suárez and Neymar. It worked, too, for a time, but after a while, when all the parts are different, it becomes clear the car is not quite the same as once it was.
That night in Paris had the air of a final curtain. Barcelona would get a new coach this summer, and soon it would have to start thinking about bringing in some new players, too, ones not to serve as understudies to its stars, but to be trained as replacements. Three weeks before, Barcelona had not just seen its European campaign ended, but a chapter of its history closed.