It was a night when Borussia Dortmund penned one of the finest chapters in their history, a seemingly unremarkable team – low on stellar names – doing something utterly astonishing. It has felt as though they have been written off repeatedly this season, starting with when they were plunged into the Champions League group of death. They won that with a measure of comfort, ahead of Paris Saint-Germain, Milan and Newcastle. After they got past PSV Eindhoven in the last 16, Atlético Madrid were supposed to be too good for them in the quarter-finals – wrong again – while here, PSG were fancied to overturn a 1-0 deficit from the first leg of this semi-final. Dortmund are at an awfully low ebb domestically, lagging fifth in the Bundesliga. But something has stirred in them whenever they have heard this competition’s aria, never more so than at the Parc des Princes. Dortmund looked like the royalty, the team that have regularly struggled to take the decisive step over the past decade or so, stunning PSG with their collective resolve, their bodies-on-the-line defending. They rode their luck. It was always going to be a part of it at this pulsating venue. PSG had hit the woodwork twice in the first leg. Here, they did so a further four times – all of the near misses coming during a second half when they threw everything they had at Dortmund. It was incredible theatre. Mats Hummels got the goal that meant everything to Dortmund, the 35-year-old rising unchallenged to head home from a corner shortly after the interval. He is a veteran of the club’s previous Champions League final appearance – the 2013 loss to Bayern Munich at Wembley. Dortmund are heading back there again and they could even meet Bayern, who are locked at 2-2 against Real Madrid in the other semi-final ahead of Wednesday night’s second leg. The Dortmund celebrations exploded like a firecracker upon the full-time whistle, the players streaming over to the section by one of the corner flags that housed their supporters, a seething mass of euphoria. The players bounced up and down in front of them for what seemed like an age; they did not want to tear themselves away. The idea now will be to emulate the Class of 97 – Matthias Sammer, Paul Lambert, Karl-Heinz Riedle, Lars Ricken et al, who conquered Juventus to collect the club’s lone European Cup. Dortmund’s joy contrasted vividly with PSG’s dejection. Luis Enrique’s team have sewn up the Ligue 1 title and they will face Lyon in the French Cup final. The treble had been on. This is a new-look team, with an emphasis on the collective in the post-Lionel Messi and Neymar era, even if one shining star has remained. Kylian Mbappé, though, will depart in the summer, the dream send-off having turned to dust. The PSG president, Nasser al-Khelaifi, had claimed when he appointed Luis Enrique last summer that the Champions League was no longer “the obsession … that is over”. It was about building a new identity, a new culture. The bottom line was that this would have cut him to the core, together with everyone at the club, even if the diehards on the Virage Auteuil mustered a tremendous ovation for their beaten players when it was all over. PSG still cannot bend this competition to the force of their desire. All that PSG could see in the first half was a yellow wall, the Dortmund players closing the spaces, moving as one. Edin Terzic had demanded his players cede nothing in between the lines and, with Hummels and Nico Schlotterbeck setting the example in defensive terms, PSG created nothing of clearcut note before the interval. When PSG had the flicker of a final pass or shooting opportunity, they rushed things, Ousmane Dembélé’s slash off target in the 31st minute a good example. That was probably as close as PSG came in the first half because Dembele had been well placed. It was not very close. The feeling nagged that Dortmund could land a counterpunch. They were composed on the ball, especially Julian Brandt, while Jadon Sancho also enjoyed some nice moments. They almost did on 36 minutes after Mbappé had failed to make a clean connection on a half chance. It was Karim Adeyemi who flicked on the afterburners, tearing the length of the field and unloading a low drive. Gianluigi Donnarumma threw out a big left hand to save. PSG battled to master the occasion. Warren Zaïre-Emery hit a post from a tight angle upon the second-half restart; he seemed to have enough of the goal to aim at after an Mbappé cross. And when Marquinhos conceded a corner with a loose back-pass, the scene was set for Hummels. Where was the marking on Brandt’s corner? Lucas Beraldo was the closest defender to Hummels and he was nowhere near tight enough. PSG ran on emotion, driven by increasing desperation. Gonçalo Ramos wasted a couple of half chances either side of a Nuno Mendes blast that slammed into the far post. The margins were against PSG, the feeling reinforced when Hummels fouled Dembélé on the very edge of the area and the referee, Daniele Orsato, opted for a free-kick rather than a penalty. It was excruciatingly tight. Ditto when Mbappé and Vitinha both struck the crossbar in the closing stages, the latter with a rasping drive from distance. Something extraordinary has driven Dortmund. The ultimate prize is in sharp focus.