On the face of it, this was a throwback, a result from the days before Ole Gunnar Solskjaer came to Old Trafford with his kitbag full of rainbows.
Manchester United were exposed at the back, toothless up front, second best all over and ill disciplined. Not only did they lose, they had Paul Pogba sent off late on for a thoroughly rotten tackle.
Yet this must be said, too — PSG are a very good side. Even without Neymar and Edinson Cavani they were deserved winners here and missed enough good chances to have the tie over before the return leg.
If Manchester United are still in it — and they are, just — it is because Kylian Mbappe scored a single goal not the hat-trick he should have got.
Kylian Mbappe opened his body up to slide a finish past David de Gea and double PSG’s advantage in the tie
The deadly forward timed his run to perfection and showed brilliant composure to slot the finish home
Presnel Kimpembe broke the deadlock with a well controlled volleyed finish into the roof of De Gea’s net
The PSG centre-back scored the first goal of his PSG career at a particularly opportune moment in the tie
What does this say about Solskjaer? Only that to have experienced a first defeat 55 days in is hardly the worst record and here was a sobering reminder that, however far United have travelled on his watch, there is still a way to go.
There won’t feel like a bright side but at least United no longer lose to inferiors, as had been happening under the previous regime.
It took one of the finest sides in Europe to beat them, one most certainly capable of winning this tournament.
United were undone by a fine team display, plus the individual excellence of two players in particular — Mbappe with his pace and goalscoring smarts which make him the best young striker in the world right now, and Angel di Maria on a revenge mission, desperate to show Old Trafford what they had missed in his brief time here.
He did, too, making both goals — and his celebrations suggested he enjoyed proving that point.
Both goals came in the second half, PSG having also had the best chance of the first.
Injury left Solskjaer reshaping United’s forward line, losing both Jesse Lingard and Anthony Martial before PSG scored. But it was at the back that they were undone — poor marking for the first goal, a mismatch of a foot race for the second. PSG dispatched them in a six-minute spell.
The opening goal came from a right-sided corner, after David de Gea had tipped round a Mbappe header from a Dani Alves cross.
Di Maria curled it in and defender Presnel Kimpembe got in behind Nemanja Matic to volley the ball past De Gea from close range.
Ole Gunnar Solskjaer watched his side lose momentum and then concede twice in the space of ten minutes
Angel Di Maria whipped in the delivery and Kimpembe lost his marker to convert with aplomb at the back post
Thiago Silva (left) wheeled away in celebration after Kimpembe gave PSG a crucial away goal to take with them
Di Maria seemed to love rubbing it in to the Manchester United fans who had given him a hard time all game
Mbappe underlined his status as one of the most lethal finishers on the planet and is still just 20-year-old
Whether he should have been on the field having committed several fouls after collecting the game’s first booking, is another matter. It was just one of the questions that deserve to be asked of referee Daniele Orsato.
That controversy, however, was put to bed by PSG’s second goal. A sublime cross from Di Maria was executed perfectly by Mbappe, opening his body to sidefoot the ball first time past De Gea.
He should have had another immediately, again put through by Di Maria and outstripping Victor Lindelof before De Gea made a fine save as the striker attempted a Messi-style low lob.
By then, Old Trafford was silent bar the raucous visitors. Capping a rotten night, Pogba made a nasty foul on Alves and Orsato at last plucked up the gumption to issue a second yellow. It had been coming. Marquinhos kept a close watch on Pogba all game and he did not like it. One brilliant first-half run aside this was a disappointing night for him, too much petulance, not enough presence.
It wasn’t Orsato’s finest hour, either. Much like United, he started off guns blazing but lost his way.
There were five players booked in quick succession early on, but then he ignored equal or greater offences that would have led to a red. United may feel hard done by as Kimpembe appeared to have got lucky — but the same could be said of Ashley Young.
He was booked, rightly, for a foul on Mbappe after 29 minutes when the young striker looked to have turned him inside out. Then, 11 minutes later, he committed a second misdemeanour that could have resulted in significant injury.
Mbappe had the best opportunity of the first half but fired his effort into the side-netting after lunging for the ball
Di Maria’s effort from just outside the box caught the attention of David de Gea but was easily kept out by the Spaniard
The first 45 minutes featured a number of flashpoints and the referee Daniele Orsato struggled to control the game
The players clashed after Ashley Young gave Di Maria an unnecessary shove off the pitch into the metal pitchside railings
Manchester United suffered an injury blow as Jesse Lingard pulled up and came off for Alexis Sanchez
Pushing is one of football’s minor offences — but not when it is an overt shove in the back of a player already travelling at high speed, on a pitch with a notoriously steep run-off perimeter and hoarding and metal fences in close proximity to the playing area.
The ball was as good as dead when Young took this liberty with Di Maria, who was sent cascading into a barrier.
He could have broken an arm or several ribs, he could have smashed his face in, or fractured his skull. Young had absolutely no control over the consequence of his action. He should have gone.
Instead, Orsato chickened out. With Young booked, either he misjudged the potential seriousness of the incident or confidence failed him. No further action was taken, despite PSG’s anger.
They had a point, too, just as Manchester United’s players did over Kimpembe, let off for reasons unknown.
Only Pogba was expelled, although 10 yellow cards were shown, just short of the record in a Champions League game.
Anthony Martial was also forced to come off with an injury and Juan Mata came on to replace the Frenchman
Paul Pogba showed only flashes of the brilliance that has typified his performances under Ole Gunnar Solskjaer
Solskjaer appealed for more from his players after PSG caught them cod at the beginning of the second half
Dani Alves had a free kick in dangerous territory but smashed his shot well over the bar at the end of the first half
United had started off at a tremendous lick, clearly under instruction to unnerve PSG. It didn’t yield much, however, a cross-shot from Marcus Rashford that tested Gianluigi Buffon and a cross from Pogba that would have needed the merest touch without the goalkeeper’s intervention.
To progress from here, United must defy history.
No team that has lost a first leg at home by two goals has gone through in the Champions League knockout stage.
Meanwhile, David Moyes remains the only Manchester United manager to win a Champions League knockout game since 2010-11.
Solskjaer? He becomes the first United manager to lose a home European tie by more than a single-goal margin. Not the history he was hoping for.
Pogba was shown a red card after picking up his second caution of the game shortly before the end of the match
The visiting supporters crammed in early and made themselves heard throughout the game at Old Trafford
The PSG players and staff came together at the end of the match to thanks the loud travelling support at Old Trafford
Mata, Solskjaer and de Gea trudged off at full time after the interim boss suffered his first defeat and United manager