Manchester United had no other choice. They simply had to win – and not only to honour the memory of arguably their greatest player. This Champions League occasion was when the Old Trafford congregation came together to remember Sir Bobby Charlton, who passed away on Saturday. The club pitched the pre-match ceremony with sensitivity and class.

After defeats in their opening two Group A ties, Erik ten Hag could not countenance a mis-fire against FC Copenhagen, the well-drilled Danish league leaders. Somehow, dramatically, United got the job done, despite being an imitation of their best selves for long spells, especially in the first half. They went to the very end – of both the tie and their nerves and, when it was over, redemption was the prominent on-field theme.

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It was there for Harry Maguire, the almost eternally maligned centre-half, who maintained his positive mini-run by scoring what proved to be the only goal. Maguire has now started and played well in United’s past three games; each of them wins, the first two coming in the Premier League against Brentford and Sheffield United.

The showstopper, though, was André Onana, who started nervously only to grow, making a key save in the 50th minute to deny Lukas Lerager. It had nothing on what he did at the last. Copenhagen had thrown forward their goalkeeper, Kamil Grabara, previously of Liverpool, for a corner in the fourth and final minute of stoppage-time and he caused a problem for United.

The Copenhagen substitute Oscar Højlund – younger brother of the United striker Rasmus – worked the ball towards the far post, a little scruffily, and there was Mohamed Elyounoussi, stooping to finish. But there, too, was Scott McTominay. He raised his boot high to concede a penalty.

The taker was another substitute, Jordan Larsson, son of Henrik, who once played for United during his glittering career. Onana sensed his moment. It has been a slog for him since his summer move from Internazionale, his errors particularly pronounced in the Champions League, contributing heavily to the losses against Bayern Munich and Galatasaray.

Now, he kept his cool as Larsson stuttered on his run-up, waiting and watching as the ball went to his left. Onana threw up a strong right hand and, in a heartbeat, the tie was won, the goalkeeper mobbed by every player in red. Does his United career have its turning point?

It was always going to be emotional. “Loved, Adored, Never Forgotten,” read the message on the card with the wreath that was placed on Charlton’s seat in the directors’ box and the lone bagpiper would tug hard at the heartstrings as he played on his walk to the centre circle. It was always possible that the occasion would be a difficult one for United to handle, particularly this United, and it was impossible to dress it up any other way – they were awful at the outset; passive, error strewn, fortunate not to concede early.

Copenhagen were able to move the ball at ease, under little pressure and, when Sofyan Amrabat hesitated and Maguire lost out to Elyounoussi, the former Southampton winger was away. From his cross, Diogo Gonçalves timed his run to guide a volley against the post.

Onana had set an unwanted tone when he dived at full stretch in the second minute for an Elias Achouri shot, which was clearly going yards wide. At first, it looked as though he was just covering himself and his post, and it was strange when the referee gave a corner. Had there been a deflection? No, Onana really had tipped it behind.

United stabilised a little after the jitters of the opening 15 minutes but it was hard to see what the plan was in an attacking sense leading up to the interval. Rasmus Højlund, up against his first professional club, looked United’s best bet, willing and aggressive at the tip of the formation.

It was flat and predictable, the crowd responding to the half-time whistle with boos. That the referee called a halt to it 20 seconds early was a mercy. United offered next to nothing in creative terms in the first half and, if Onana’s distribution was erratic, the passing from those in front of him was no better. Sergio Reguilón had a glorious opportunity to send Marcus Rashford clean through on the counter in the 44th minute and it was not a difficult pass to make. Instead of playing it into the space in front of Rashford, he undercooked it.

Ten Hag introduced Christian Eriksen for the off-colour Amrabat at half‑time and United improved, although they needed Onana to deny Lerager after a break from Viktor Claesson.

The impressive Eriksen forced Grabara into a fine save while Rashford almost got through twice with some electric running, only to cross his wires on the second occasion, his touch jarringly heavy. The substitute Alejandro Garnacho would also fluff a glorious one-on-one chance after Bruno Fernandes had released him.

It was Eriksen who made the goal, whipping over a cross from the right after Copenhagen had half‑cleared a corner, and it was Maguire, powering in front of Rasmus Falk, to head home. Maguire whipped up the crowd, made a heart with his hands and beat the badge on his chest. Garnacho would blow another big chance on 78 minutes, Grabara denying him and McTominay guiding the rebound inches wide. The scene was set for Onana.