On a gripping, occasionally frantic night at the Parc des Princes, Paris Saint-Germain and Barcelona produced a game that felt like the opposite of the shared “Barça DNA” Xavi had spoken about in the build-up to this quarter-final.

Never mind control, patterns and a fight for space. This was an increasingly wild game, building from a mannered start into a second half of sweeping mob-handed attacks, feather-light defending and chances that simply came and went, posts clipped, shots blocked in desperation.

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By the end Barcelona had done enough to deserve their 3-2 lead heading back to the Camp Nou. Xavi spoke about control afterwards and said he was “very happy” with the defensive work of his players. But nobody who watched the more unbound parts of this game would see anything other than goals on both sides in the second leg. Frankly this could have been anything.

Security around the Parc des Princes had been beefed up before the game in response to the threat from the terror group Islamic State. Drones circled the sky. Heavily tooled-up police occupied the corners. Paris 2024 is still planning a mass city-centre Olympic opening ceremony a hundred days from now. It keeps on being scaled back. Expect a little more of that from here.

The Parc was rocking at kick-off, drenched in a lengthy pre-match Star Wars-themed son-et-lumière show that involved playing the Imperial March quite a lot, and climaxed with the unfurling of an enormous militaristic Yoda banner. And why not?

Barcelona had Frenkie de Jong back from injury. PSG had Marquinhos covering at right-back again and Marco Asensio starting through the centre of the attack.

The home team set out to stretch the pitch early on, wingers staying very wide, trying to disrupt the central yellow box. But it was Barça who had the first real sight of goal on 20 minutes after some laboured spells of PSG possession. Raphinha, who had a wonderful game here, won a corner on the right. Robert Lewandowski leapt above Gianluigi Donnarumma’s flailing fist to send a  looping header towards goal, only for Nuno Mendes to hook the ball clear.

PSG were stodgy on the ball, always funnelling it back towards the two obvious outlets, Kylian Mbappé, who did very little in this game, and the more sprightly Ousmane Dembélé. Luis Enrique has been a convincing coach of PSG. The fans love him. The team are on a 27-game unbeaten run. Denuded of its basking superstars, this PSG project has begun to resemble an actual sport-style team-type object, baroque attacking riches sacrificed for energy and a more basic set of patterns.

Barça looked the more supple attacking unit, and they duly took the lead on 35 minutes with a goal made and scored by their three-man front line. Lewandowski broke a flimsy challenge close to halfway and shuttled a pass out to Lamine Yamal on the right. His cross was deflected back towards Raphinha, who finished beautifully, lofting the ball beyond the covering blue shirts into the top corner.

Luis Enrique rejigged during the break, bringing on the jet-heeled Bradley Barcola for Asensio and shifting Dembélé to a roving No 9 role. It worked almost immediately, Dembélé cutting inside and lashing a thrilling left-footed shot high into the net past Marc-André ter Stegen.

Within five minutes of the restart the game had turned on its head. PSG’s second goal was beautifully constructed, Fabián Ruiz playing a lovely little delayed pass to meet Vitinha’s run through the inside left channel. He slid the ball into the corner of the net.

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Faced with some sustained aggression Barcelona’s entire defensive structure had simply dissolved like an over-dunked digestive biscuit. For a while they were clinging on, thrown by the more potent angles created by Dembélé’s runs from the centre. Barcola veered in from the right like a downhill slalom skier and saw a powerful shot palmed up on to the bar.

Xavi responded by sending on João Félix and Pedri, and just as quickly Barcelona were level. This was a beautiful goal, albeit conceived and executed under zero pressure from the PSG midfield. Pedri had time to loft a lovely, delicate pass down the centre. Raphinha’s volley into the corner on the run was a dreamy, high-craft piece of finishing.

By this stage Barcelona had Ilkay Gündogan playing up front with Lewandowski, with Félix and Pedri just behind, and there was a hugely engaging sense of chaos in the air. Dembélé shimmied through on the left and clipped a shot on to the post.

But with 76 minutes gone it was 3-2 to the visitors. Andreas Christensen (having only just sneaked on to the pitch) headed straight in from a corner with his first touch of the ball, again unmolested by any obvious defensive attention. Barça hung on to their lead at the death, but only just. This one has plenty of road left to run.