Ever since arriving in England in 2013 and enjoying an impressive season with Southampton, Mauricio Pochettino has been a man in demand.

That body of work meant he was courted again as the years went on.

In 2018 Spurs fans were incandescent when Manchester United made their pitch for him to move to Old Trafford as the replacement for the sacked Jose Mourinho.

That move did not materialise but when Ole Gunnar Solskjaer was dismissed in November the interest that followed from United was real - and almost certainly mutual. A few months earlier Tottenham had tried to tempt the Argentine back, unsuccessfully, with Pochettino eventually staying at Paris St-Germain to continue his project there.

He has spoken to United executive vice-chairman Ed Woodward at least three times in the past few years and he knew he was seen as the ideal candidate by Sir Alex Ferguson and some of the former players with whom chief executive Richard Arnold talks regularly. The majority of decision-makers in Manchester had favourable words to say about him, his tactics, his development of players and how he represents the clubs he has managed.

But others considered his achievements insufficient and told Arnold so. In the USA, the owners were eventually more impressed by the CV of Ajax manager Erik ten Hag, and confused by what Pochettino had done at PSG.

Now, with United appearing close to confirming the Dutchman as their first choice, Pochettino must come to terms with the fact he seems likely to be overlooked for a job that, at times, has seemed his destiny.

Not only that but his PSG future remains uncertain. So what next for a man who has been one of European football's hottest managerial properties for the past decade?

A sliding doors moment in Madrid?

At many of Europe's biggest clubs, success in the Champions League can define a manager's status.

Carlo Ancelotti may have guided Real Madrid to within sight of the Spanish title this season, but that did not stop speculation that defeat by Chelsea in the quarter-finals could cost him his job.

Pochettino's PSG are even further clear in their domestic league but what is most likely to be remembered about their season is the way they imploded in the second leg of their last-16 tie against Real Madrid, squandering a 2-0 aggregate lead in a breathless, Karim Benzema-inspired 17-minute period at the Bernabeu last month.

That defeat, on the back of a really good performance for most of the tie, seemed inexplicable. Illogical.

"I feel deeply wounded," Pochettino said that night. Hundido was the Spanish word used - sunken, hollow. He felt that way for a long time after, longer than when Spurs lost the 2019 Champions League final to Liverpool. Being in that final was a little football miracle, but this was football madness.

Blaming the referee for not giving a foul against Benzema when he made Gianluigi Donnarumma fall over for Madrid's first goal was a way of trying to find an explanation.

A few days later Pochettino had to conclude that the first 150 minutes of the tie produced the best football of his PSG tenure, but the lack of emotional control in a 20-minute spell amid an extraordinarily feverish atmosphere at the Bernabeu had to be analysed, and that assessment has become a priority for the following months. If he is allowed to continue.

When a football 'disaster' occurs, PSG tend to burn the whole house down. The chairman, Nasser Al-Khelaifi, has travelled to Qatar and will take decisions at the end of the season that will affect the future of sporting director Leonardo and, many suspect, Pochettino. Neither of them knows anything about it yet.

Despite what is sure to be a first league title of his career this season, if his dismissal does come to pass it will leave the Argentine in an unfamiliar position. Real Madrid will always be an option because their president Florentino Perez is a great admirer but Ancelotti has turned around the toughest part of their season and the suspicion is he will be given more time.

So what next? A period of reflection could be required for Pochettino. One of his favourite sayings - "let things flow" - may be an apt way of looking at things.

Are PSG 'unmanageable'? And has that cost Pochettino?

The conundrum Manchester United's decision-makers will have been weighing up, you would suspect, is how much they should judge Pochettino on one nightmarish period of 17 minutes in one Champions League match.

A fairer assessment would be to analyse the job he has done - is doing - at a club that has at times seemed almost unmanageable.

The fact he spent 14 months in a hotel perhaps spoke to his own understanding that no PSG manager stays for long. But the 50-year-old has now moved to a flat and, whatever the critics say, has made strides forward with PSG.

For long periods of the Real Madrid tie he achieved what many felt was impossible - the creation of a functioning, coherent unit that got the best out of his three star attacking players.

Lionel Messi, Neymar and Kylian Mbappe are all at their best when the team is set up to get the maximum out of their individual brilliance, so how do you make that work when all three are involved?

With a player like Mbappe you need a team that can play with a high rhythm and that looks to attack spaces. With Messi you have to give him freedom, play slower, build from the back, have the players close together and effectively organise your team around him. And if you have Neymar, with all his genius to beat defenders, you need a team that allows him to do his thing, often unpredictable, and be alert to those moments when he loses the ball.

The manager has to put all that together.

Before the Madrid meltdown, Pochettino had, during that tie, got as close as he has come to making an unworkable situation workable.

His predecessors at PSG, Thomas Tuchel and Unai Emery, both had a go at trying to find a way of playing that would accommodate two superstars in the shape of Neymar and Mbappe.

Bearing in mind Emery and Tuchel failed to maximise their potential yet still managed to win European honours with their next clubs (Chelsea and Villarreal respectively), it might be safe to assume the problem stems not from the coach but from the club itself.

One of the key themes that emerged from my conversations for this article with people who have been at the club in the past is that PSG's players may be excellent footballers but they are also effectively brands, whose success and development ensures the exponential growth of the main brand - the club. It is the manager's job to ensure the success of both elements.

The squad contains the captain of the Netherlands, Argentina and Brazil as well as the former Spain captain. That is a lot of huge personalities who grew to be so by leading, by being ahead of others. And they meet in a changing room where naturally plenty of people want to be heard.

This 'Disneyworld' approach is not dissimilar to the former Galactico philosophy employed by Perez at Real Madrid.

PSG is, it seems, not built with football as its main priority but rather as a vehicle to show the world the Qatari owners' ability to put together massive projects.

Often, though, the choices are affected not by what is needed but have more to do with the club linking themselves with some of the best-known players around. That policy has created an excess of central midfielders, seven left-backs at some point this season, and signings like that of Donnarumma in place of a perfectly adequate Keylor Navas, for no reason other than that he was available.

When the priority is brand image and not football, then inevitably the role of the coach is never going to be that important either. "At PSG there are so many influences," Tuchel explained after he left the club.

Every manager who enters the PSG world is convinced he can turn things around, that he can find the right balance between the needs of the stars and those of the team. That he can change what is now an ingrained philosophy.

But to play the stars together is completely different to saying they can play well together.

Kylian Mbappe (centre), one part of PSG's high-profile attacking trio, is likely to leave for Real Madrid this summer, although the French club are pushing hard to keep him

So what can the coach do about it all? How can he create the right conditions to maximise the potential of the side? He has no choice other than to understand what kind of club it is and find the right amount of intervention, which is much less than in most teams.

"Can the boss be allowed to have a go at them, or do the players rule?" legendary France striker Thierry Henry asked recently. "If, at the top, the coach cannot be strong in terms of what he wants to do and how he likes to play, then it becomes difficult."

In the Paris press there is almost a daily crisis, many of them imagined. "I like football," Tuchel has said. "But in a club like this one, it is not always about football. Sometimes I do a substitution and it's a news story for two weeks. And I tell myself: I just want to coach!"

PSG are described by someone who deals regularly with them as a "club with feet of clay, outwardly strong but with severe weakness under the surface".

And when the wheels fall off it becomes the coach's fault as no-one looks at the bigger picture.

So, is it fair when Henry says "Pochettino is not allowed to be Pochettino at times with that team"?

The man himself felt that his main task was all about creating harmony. How do you keep everyone happy? Forget about offering a dogmatic imposition of ideas or a level of training that is demanding and intense. It is about something else: making sure their heads are in the right place, that the common ground is found.

And he has to think beyond the "now". It was a misunderstanding that led to Messi being substituted in a match against Lyon in September with the score at 1-1. Messi told a member of the coaching team that he was OK when he was seen stretching his knee. That message never reached Pochettino, who replaced him following advice from the doctor, only to be told by the player - when asked if he was OK - that he had already told him he was.

Messi appeared unhappy when taken off by Pochettino in a game against Lyon in September

The manager was thinking of upcoming Champions League games and the ramifications of seeing someone like Messi, recently arrived, getting seriously injured. Messi missed the following two games and a few weeks later he recognised in private that the manager was right to replace him.

There are occasional differences of opinion, which is a long way from saying there is a situation described by the media as explosive.

In fact, different sources from the changing room claim there have been zero conflicts, which is a major achievement when the balance is so fragile. A player being replaced and putting on a funny face is not considered a conflict as the issue did not linger.

But, ultimately, in order to maintain harmony everyone has to play. And why wouldn't he use PSG's three brilliant footballers? They cost a lot because they are excellent.

Generally, a team can just about sustain and indulge a superstar, an anarchic or creative genius, but if you end up with three of them in your line-up you shouldn't be too surprised when what follows is an anarchic game, and it affects how you defend.

"If you want to win the Champions League, you cannot in the modern game defend with seven players," Henry told CBS. "It's impossible. I don't care who you are."

Against Real Madrid, the trio showed they are capable, when the stakes are high, of thinking and working as one and following the manager's path. They just couldn't do it for 180 minutes.

One of the main things Pochettino has learned in his most recent years as a manager is that training top players is an art form. At Spurs he found a team in their comfort zone. The players who were signed were hungry for titles, willing to be moulded, accepting the leadership of the manager.

But at PSG he has footballers who have won everything.

His intention in Paris has always been to help them be a little bit better if possible, to fit within a collective idea, and mostly to keep them ready for the big moments. He originally tried to push the players to do a little bit more each time in training, to help them develop physically, but science and injury prevention suggested he should actually reduce their workload, not increase it. He had to adapt.

Those are the lessons from the PSG adventure. For now at least, Pochettino will not get his chance at Manchester United and will continue to try to establish calm amid the Paris chaos.

Will he be disappointed? Probably. Might he have escaped a jump from the frying pan into the fire, given the Old Trafford club's own structural issues? He would have relished that challenge.