Four years on, Barcelona are back in the Champions League quarter-finals. On the edge in footballing and financial terms, this was the game they just could not afford to lose but while all the talk had been of obligation, Xavi Hernández had described it as an opportunity, and so it was. High on Montjuic, it became a night to be enjoyed and remembered. Not least, perhaps, as the first of many European occasions for three exceptional La Masia kids: Pau Cubarsí, Fermín López and Lamine Yamal, a defender, midfielder and forward, aged 17, 20 and 16, who were decisive in the undoing of Napoli and offer the promise of a better future, the pessimism pushed aside here. Vindication took its place.

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“We were the buffoon of the Champions League, everyone said,” Xavi insisted afterwards. “And now what?” Now, for Friday’s draw, where few expected them to be. These have been difficult times in this temporary home, an Olympic stadium Barcelona do not feel as their own. With Gavi, Pedri and Frenkie de Jong all out and a coach who has already announced his departure when the season ends, the fear had grown that it might in effect end here. Instead there were celebrations, and for good reason: Barcelona’s 3-1 win, 4-2 on aggregate, was deserved, the shot count reaching 24.

Ultimately the start, when they scored two inside 15 minutes, was enough. And when it looked like it still may not be, Amir Rrahmani putting Napoli back in it, the game going into the final minutes still undecided and the nerves naturally growing, Sergi Roberto and Ilkay Gündogan combined superbly to set up Robert Lewandowski to roll in a late third. Asked if the first half an hour was Barcelona’s best 30 minutes all season, Xavi replied: “Yes, and the last 30 as well.”

It had been some start. Osimhen was almost in on eight seconds, Yamal had the game’s first shot on 58 of them and after just three minutes Napoli’s Nigerian forward raced clean through, a late flag saving him the embarrassment of the poor finish. Five minutes after that, Cubarsí produced a superb tackle to prevent Osimhen escaping once more, the timing impeccable, and within seconds López pulled a shot wide at the other end. Soon, López was in again, released by Cubarsí’s outrageous pass. Bringing the ball down, beyond the defence, he lifted it over Alex Meret but also the bar.

He wouldn’t be denied. The game was still only 12 minutes in; four minutes more and Barcelona had scored twice. First Cubarsí, Cancelo and Raphinha combined to work an opening, Lewandowski let the ball go and López slotted home. Then a lovely flick from Yamal over Stanislav Lobotka’s head on the edge of his own area got him up and running. He reached the half way line and played in Raphinha. The Brazilian’s shot came back off the post: still on his knees, thumping the turf, head down in despair, he missed Cancelo putting the rebound in the net.

This place exploded, loud and fun, which hasn’t always been the way. Just before the half hour, though, Napoli scored, a move that began with Rrahmani ending with him too. Matteo Politano pulled it back and the defender, still running, delivered a perfect shot beyond Marc-André ter Stegen. Khvicha Kvaratskhelia flashed just wide at the start of the second half and then Politano beat Cancelo only to be blocked, pressure applied and a hush momentarily falling. It was broken by a collective intake of breath when Cancelo’s clearance fell to Zambo Anguissa, but he could not scramble the shot goalwards.

Struggling a little to control this, it felt like Barcelona might need another goal, and they almost got it when Meret pushed away a Raphinha free-kick and, from the corner, a Lewandowski header. Yamal thought he had scored from the rebound but was offside. With Oriol Romeu and Sergi Roberto introduced on the hour, Barcelona did manage to get hold of the ball again, back on top, Meret pushing away an effort on the turn from Gündogan. Raphinha was the next to be denied by Meret before Yamal, teed up by the German, curled fractionally wide.

Napoli’s rebellion had not lasted long and when they did create the one chance they needed, a late lifeline, substitute Jesper Lindstrøm headed wide from six yards. And then there were Sergi Roberto, Gündogan and, finally, Lewandowski to send everyone back down the hill happy.