Barcelona's unbeaten start to the season ended with a 4-2 defeat to Paris Saint-Germain on Tuesday, but Hansi Flick's side showed enough resilience and attacking quality to suggest they are moving closer to Europe's elite.
PSG struck twice in the closing stages after Lamine Yamal's equalizer to secure a dramatic UEFA Champions League victory at the Parc des Princes, maintaining their perfect record in the competition with three wins from three matches.
For Barcelona, the result was a painful reminder that domestic dominance does not automatically translate into European success. Yet their response after falling behind twice offered encouragement as they pursue the major trophy that has eluded them under Flick.
Midfielder Pedri had said before the match that the encounter would reveal where Barcelona stood in Europe. The result suggested the Spanish giants still have ground to make up, although they demonstrated they could challenge the reigning European champions for long stretches.
Barcelona arrived in Paris having won every match across all competitions this season. Their attacking firepower had overwhelmed opponents in LaLiga, but questions remained over whether Flick's aggressive approach could leave his team vulnerable against Europe's strongest sides.
Those concerns resurfaced early in Paris, where PSG imposed a relentless tempo and repeatedly tested Barcelona's defensive organization.
Khvicha Kvaratskhelia struck the post in the second minute, while goalkeeper Joan Garcia produced a series of outstanding saves to keep the visitors in the contest. He denied Ousmane Dembele and Desire Doue before making a double stop against Ferran Torres and Fabian Ruiz in the 29th minute.
PSG's pressure eventually paid off in the 38th minute. Joao Neves intercepted a pass from Yamal in midfield, and the ball fell to Doue, who cut inside near the edge of the penalty area before firing a powerful right-footed shot into the bottom-left corner.
Barcelona nearly responded immediately, but goalkeeper Matvei Safonov denied Fermin Lopez after a through ball from Pedri, with Willian Pacho clearing the rebound.
The visitors also had to contend with personnel problems. Marc Bernal was a surprise starter in midfield, while defensive absences involving Eric Garcia and Jules Kounde complicated Flick's preparations. PSG, meanwhile, lost Dembele to an apparent hamstring injury in the 20th minute, with former Barcelona forward Torres replacing him.
Garcia remained Barcelona's most important player during the first half, but the visitors gradually found their rhythm after the break. He initially denied Achraf Hakimi in a one-on-one situation in the 52nd minute before Barcelona finally found a breakthrough.
Three minutes later, 19-year-old Xavi Espart marked his first Champions League start with an equalizer. After exchanging passes with Lopez, the teenager raced into the penalty area and sent a low shot past Safonov, displaying composure well beyond his years.
The goal changed the momentum. Barcelona began to enjoy more possession, while Yamal emerged as the focal point of their attack after a relatively quiet first half.
His incisive passing and ability to carry the ball into dangerous areas unsettled PSG, giving the visitors a spell of control that had been missing earlier in the match.
Barcelona's improvement, however, did not prevent PSG from regaining the lead.
In the 72nd minute, Lucas Hernandez rose above the defense to meet Doue's corner and powered a header into the top-right corner. The goal came shortly after Torres had struck the post, underlining the hosts' continued threat despite Barcelona's growing influence.
Flick's side refused to fold. Yamal restored parity in the 79th minute after Warren Zaire-Emery, who had just entered the match, misjudged a headed clearance. The Spanish teenager collected the opportunity, drove into the penalty area from the right and scored from a tight angle to make it 2-2.
But Barcelona's hopes of leaving Paris with a result quickly evaporated.
Two minutes later, Vitinha controlled a loose ball on his chest outside the penalty area and struck a right-footed half-volley into the bottom-right corner to put PSG ahead again.
Ruiz completed the scoring in the 86th minute, meeting Hakimi's low cross at the far post to seal a 4-2 victory for Luis Enrique's side.
The late goals exposed Barcelona's vulnerability under sustained pressure, but the defeat also carried signs of progress compared with the problems that undermined their previous two European campaigns under Flick.
Indiscipline and susceptibility to counterattacks had proved costly in earlier continental setbacks. Against PSG, Barcelona showed greater resilience and the ability to recover from difficult moments, even if they could not maintain that resistance until the final whistle.
Captain Raphinha insisted the performance offered reasons for optimism despite the outcome.
"Despite today's result, we competed well," he said on Movistar+, adding that the match was a useful test and demonstrated Barcelona's ability to compete.
Flick also remained positive while acknowledging PSG's superiority.
"We need to analyze the match, but I saw some very good things and things that we should build upon. I don't want to be negative; I'm feeling positive," the German coach said.