It was probably always as much a barometer for Arsenal as anything else. How could they compete with Paris Saint-Germain, one of the Champions League powerhouses? Very good, was the answer.

On a night to reinforce the collective belief in the greater challenges ahead, especially those that will surely come after the group stage of this competition finally reaches its climax, Arsenal showed their mettle in the physical duels and a cutting edge and drive to surprise the home crowd. .

Kai Havertz scored with a towering header and when Bukayo Saka swung a free-kick through a mass of bodies inside the PSG area and past the visually impaired Gianluigi Donnarumma in the 35th minute, Arsenal knew it was theirs to lose.

By the end, they would survive a few scares; a PSG goal could have made it interesting. But there was a general feeling of too many touches from PSG and not enough bite. It was Arsenal who made the statement.

Arteta remained in the XI that started Saturday’s win over Leicester and the tactical battle was enthralling. Arsenal battled with Havertz and Leandro Trossard at the top of their formation – each had the license to drop – while it was noticeable from the start that Riccardo Calafiori wanted to move from left-back into central midfield.

How much did the outcome really matter? It’s hard to see either of these teams failing to progress and there’s a feeling that no one knows yet where the danger lies in this reimagined group stage. The PSG ultras were in the mood to intensify the occasion. They bounced like one seething mass 25 minutes before kick-off; as always, the drum sound from their enclosure was constant.

It was the Arsenal support who were able to celebrate in the 20th minute. After all the early complexities, it was an old-fashioned move with an old-fashioned finish that broke the deadlock, with Havertz rising high to reach Trossard’s chipped ball from inside the left in front of Donnarumma. It was brave of Havertz; he risked damage when Donnarumma took his colossal body off his line.

Luis Enrique had made a statement before the match, leaving Ousmane Dembélé out of his PSG squad; the pair clashed after last Friday’s victory over Rennes. The manager accused Dembele, who is probably his most prominent player, of disrespecting the team and it reinforced the message around the club these days. No more Galacticos. Less ego; more effort and unity. That said, it was a move that undoubtedly weakened PSG.

PSG could point to a Nuno Mendes shot that hit the outside of the far post and an Achraf Hakimi effort that saw David Raya go over his own crossbar. The first half was further from Arsenal. They were determined to show why Luis Enrique had described them as the best team in Europe without the ball. Calafiori and Jurrien Timber won big one-on-ones against Hakimi and Bradley Barcola respectively; Gabriel Magalhães celebrated as he ushered the ball in for Warren Zaire-Emery.

But it was really about what Arsenal did in the final third before the break. Saka had curled wide early on after a pass from Calafiori, while Havertz crossed dangerously from the byline, with no one in red making the necessary run. Arsenal turned the screw at 1-0 and it was yet another set piece that gave them a cushion.

PSG were accused of not doing their homework when Saka converted a low free-kick from the right. One by one, Arsenal’s players attacked the ball and found themselves in Donnarumma’s eyeline; first Gabriel Martinelli, then Gabriel and Thomas Partey. It just went all the way through and in. It was terribly soft from a PSG point of view and they were grateful it didn’t get worse shortly afterwards, with Donnarumma blocking from close range from Trossard.

PSG wanted Vitinha to dictate for the back four; he had runners on either side of him in Zaire-Emery and João Neves. Vitinha’s appreciation for his perspectives and possibilities, often in the tightest of spaces, is wonderful to see. More generally, it was possible to see the style in PSG. They needed more than decoration.

Arsenal should have made it 3-0 early in the second half, with chances for Martinelli and Havertz. Martinelli’s was the big one. It was a beautiful move from right to left, starting with Saka, who was excellent from the start – so explosive, so direct – and through Trossard and Havertz. Martinelli was all alone and turned straight towards Donnarumma. The goalkeeper would be grateful that Havertz did the same with a downward header from Martinelli’s cross.

Arteta brought on Mikel Merino as a substitute for a late debut after the summer signing finally recovered from a shoulder injury, but PSG pressed on the front foot in the closing stages. Arsenal seemed happy to invite them, to keep what they had, and there were nervous moments. Neves sent a corner down and against the crossbar, while Raya made a slightly risky parry from Lee Kang-in’s curler.

Martinelli would be denied again by Donnarumma, a fine save from the goalkeeper on his left, and PSG knew it wouldn’t be their night when a loose ball struck Calafiori’s hand and the referee, Slavko Vincic, ignored their penalty claims.