As the final whistle blew on this pulsating, perplexing game you could see the two sides stumbling around in a kind of daze, still trying to process things. Wondering how their combined efforts and errors had resulted in just a single goal. Wondering whether – for all their boldness and brittleness – this really could be Borussia Dortmund’s year.

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Niclas Füllkrug’s first-half goal ultimately settled matters, even if very little felt settled during a subsequent hour during which Gregor Kobel’s goal seemed to be doused in holy water. Kylian Mbappé had 52 touches, three shots on goal, hit the post and still left empty-handed. But perhaps Dortmund had earned their luck too. They could quite easily have scored more themselves after a performance of utter conviction and a maturity that has not always been their hallmark. “The result is OK,” Edin Terzic said afterwards, refusing to get carried away. “We have a small lead and a good opportunity.”

No miracles, then, but a resurrection of sorts. Did anyone seriously believe, during his long and lonely calvary on the Manchester United fringes, that Jadon Sancho still had a night like this in him? Did Sancho? But here he was, reformed and rehomed, the best player on the pitch by a distance, his 12 dribbles the most in a Champions League semi-final since Lionel Messi in 2008, his confidence seemingly growing with every one. Forsaken by United, forgotten by many others, this was a reminder that at his best Sancho belongs on the very biggest stage. All of a sudden, Gareth Southgate has a decision to make.

On the other flank Ian Maatsen probably got the better of a fascinating duel with Achraf Hakimi, while the centre-halves Nico Schlotterbeck and Mats Hummels were sublime. For Paris Saint-Germain, Vitinha had a smart game in midfield, and but for the interventions of Marquinhos in defence they could have been facing an even wider deficit at the Parc des Princes next Tuesday. But ultimately this game turned on chances taken and chances not taken, on the coats of varnish that denied both Mbappé and Hakimi an equalising goal.

Füllkrug’s goal, to be fair, had been coming, with Dortmund finally settling after PSG had started the brighter. For half an hour Sancho had looked sketchy and skittish, longing to try things but lacking the conviction. Finally, he took on two defenders on the edge of the area, cut the ball back for Julian Brandt, and though the shot was deflected away this very act of audacity seemed to fill Dortmund with the spirit of enterprise, remind them of themselves.

A few minutes later Schlotterbeck was clipping the ball over the top for Füllkrug, who took two sumptuous touches: one to control with his right foot, one to bury a low finish across Gianluigi Donnarumma with his left. Now the Yellow Wall roared, heaved and swayed, smelled blood. Only Donnarumma’s sprawling dive stopped Marcel Sabitzer from making it 2-0. The break seemed to come at a good time for PSG, who emerged from the dressing room with far more control and purpose.

Early in the second half Mbappé capped a stinging counter-attack with his trademark curler from the corner of the area, clattering off the inside of the post. Seconds later Hakimi had another go and hit the inside of the other post. A few minutes after that Marquinhos put in a wonderfully disguised low cross that Fabián Ruiz somehow managed to head wide. As in both legs of their quarter-final against Atlético Madrid, Dortmund were living off charms and wishes.

The problem for PSG – and really, not at all a novel problem – was that in between those wild flourishes Dortmund were essentially walking the ball through them at will. That familiar lack of defensive intensity up top was inviting pressure further back. Just before the hour Sancho wafted at warp speed to the right byline and cut the ball back for Füllkrug, who missed a chance far easier than the one he scored.

It had been a sweltering day in Dortmund and as PSG began to surge again, to build the waves of pressure, you could see the Dortmund players trying to catch their breath. Perhaps there was an argument that Terzic could have turned to his bench earlier, but their attackers were having a storming game, and was this really the moment to bring on a fresh defender against Mbappé and friends?

Nobody really expected Dortmund to come this far. Facing PSG again next Tuesday will be an entirely different challenge, a test not just of skill but of courage in the face of what will almost certainly be a merciless assault. Dortmund’s victory secured their qualification for next season’s competition, Germany now guaranteed a fifth Champions League spot. But they are not quite done with this campaign yet.