Solskjaer looks dejected with players Alexis Sanchez, Juan Mata and David de Gea after the loss

Ole Gunnar Solskjaer's first defeat as Manchester United manager was a case of reality finally kicking in among all the fantasy - and the outcome of years of mismanagement at Old Trafford.

Solskjaer's impact as interim boss has been so great that there was a real air of expectation in the stadium before Tuesday's Champions League meeting with Paris St-Germain.

It was all a sharp contrast to when the last-16 draw was made and the cloud of Jose Mourinho's final days in charge loomed over a United side viewed as the plum Premier League pick for Europe's elite.

The resulting 2-0 defeat stands as the first blot on Solskjaer's United managerial record - 10 wins and a draw from 11 games before PSG came to town - but this was not a loss 90 minutes in the making; it was one fashioned over several years.

And that is why - disappointing though it was to be brutally brushed aside by a PSG team missing superstars Neymar and Edinson Cavani - this loss should not figure large in United's calculations about whether to appoint the Norwegian as the long-term successor to Mourinho.

Solskjaer may have been the man in the technical area, and of course he takes some responsibility, but the wider picture, ruthlessly exposed by PSG, is a portrait of just how far United have been allowed to drift and fall behind.

United were unlucky to lose Jesse Lingard and Anthony Martial to injury but PSG's strength, and the use of their own financial firepower, allowed them to make light of the loss of Neymar and Cavani.

The final scoreline could have been a lot worse had David de Gea not made important interventions - and it would be optimism gone mad to suggest the second leg in Paris will be anything other than a completion of the formalities.

It is to Solskjaer's credit, accumulated over those 11 games, that there was any optimism at kick-off - but the longer the game went on, the more it waned. When the final whistle blew, the thousands of empty red seats told their own story.

United have been allowed to fall into such disrepair on the back of flawed managerial choices, instability, and a badly structured transfer policy overseen by executive vice-chairman Ed Woodward that they can no longer take their place at Europe's top table.

PSG are fuelled by fierce ambition and Qatari billions and yet even they are struggling to establish themselves among the big Champions League players - but on this evidence they are still far in advance of United.

United are a huge European and global club in many aspects but not in the one that counts most: on the pitch.

Few United players, on this evidence, would get anywhere near PSG's team. A case could be made for De Gea and Paul Pogba but even United's area of real strength, in attack, is eclipsed by the riches available to PSG boss Thomas Tuchel.

United's defence has been key to the fine run under Solskjaer but they cracked under stress here, especially early in the second half when they were cut apart at will and PSG threatened to take the tie out of sight.

The home fans did their best to create a crackling atmosphere on the club's return to big Champions League nights, although the goading of Di Maria only coaxed a stellar performance from the Argentine, who created both goals for Presnel Kimpembe - who was lucky to still be on the pitch after earlier offences - and Kylian Mbappe.

Football has the capacity to produce miraculous comebacks but it stretches the imagination to think this United side, deservedly back in the top four at home but miles off the pace in Europe, can claw this back.

Some of United's recent flawed decision-making was illustrated by the performance of Alexis Sanchez, a hugely expensive liability who might as well have stayed in his seat among the substitutes for all the good he did after coming on just before half-time.

And when the crunch came and the starting selection was made, Solskjaer went with Marcus Rashford and Martial rather than £75m Romelu Lukaku - a decision that says much about the striker's place in the manager's plans.

The chasm between United and PSG only underscored the importance of Woodward and his boardroom colleagues finally getting a big decision right when it comes to choosing their next manager and the path forward.

Optimism has rightly risen amid Solskjaer's renewal of United, but this was a graphic illustration of just how far away they are from where they want to be.

Is appointing Solskjaer a gamble or a question of Woodward and the board holding their nerve and moving away from the star-struck recruitment policy that led to Louis van Gaal and later Mourinho?

Whatever it is, the manner in which they were outclassed and dismissed by PSG only emphasised the fact that this time they cannot afford to take another wrong turn or they risk falling even further behind Europe's best.