PSG vs. Real Madrid holds the key for Mauricio Pochettino's future, with Man United hovering

Mauricio Pochettino has enjoyed a period of calm at Paris Saint-Germain in recent weeks, but with the return of the Champions League and a round of 16 first-leg tie against Real Madrid on Tuesday, it's time for the former Tottenham manager to strap himself in for the turbulence that lies ahead.

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There is no escaping the fact that Pochettino's reign as PSG coach will be defined by what happens in the box-office tie against Madrid. If PSG are able to dump out Carlo Ancelotti's LaLiga leaders, it will generate belief at Parc des Princes that the club's array of superstars -- including Lionel Messi, Kylian Mbappe and Neymar -- can finally go all the way and win the Champions League this season while, at the same time, giving Pochettino control of his own destiny.

But if PSG suffer the ignominy of elimination at the first knockout stage, regardless of the pedigree of their opponents, Pochettino will know that his days at the club will be numbered. Failure in Europe's biggest club competition simply isn't tolerated by PSG's demanding owners. Just ask Thomas Tuchel, who was dismissed as coach less than six months after guiding the club to their first Champions League final in 2020 -- a 1-0 defeat to Bayern Munich.

The PSG melodrama is usually enough of a distraction for any coach that has taken on the challenge of working under intense pressure at the same time as attempting to mould their individual stars into a properly functioning team, but Pochettino must also deal with the constant speculation linking him with a return to the Premier League as Manchester United's next permanent manager.

Sources close to Pochettino have told ESPN that a move to Old Trafford appeals to the Argentine, who is fully aware that coaching PSG can never be regarded as a long-term project. But while there is a high-profile opportunity to take over from interim boss Ralf Rangnick at United this summer, he is under contract in Paris until the end of the 2022-23 season and has more chance right now of winning the biggest honours with the French champions than he would at United.

And, as reported by ESPN on Thursday, United's list of potential new managers extends beyond Pochettino, with Spain coach Luis Enrique and Ajax's Erik ten Hag also under consideration.

So the road ahead for Pochettino is a confusing one. There will never be any genuine job security at PSG, but the obvious route out could be taken by somebody else, so the only way to deal with his situation is to keep winning in Paris and hope that any success along the way enables him to decide what happens next, rather than have his fate taken out of his hands by failure.

Despite a four-game winning run in Ligue 1 that has PSG 13 points ahead of second-placed Marseille, Pochettino's team go into the tie against Madrid with question marks hovering above their ability to win when it really counts in the Champions League.

Are PSG tested enough in France to be able to step up to the kind of games that await against Real Madrid? Is Lionel Messi still capable of deciding a big match at 34, given the former Barcelona forward has only scored seven goals in 20 games for PSG? And can Pochettino ever rely on the 30-year-old Neymar, now training again after being out with an ankle injury since November, to shine when the club needs him most?

PSG's 2-1 defeat at Manchester City in the group stage last November offered the biggest pointer to all of those questions, with the Premier League team dominating at the Etihad. Although Mbappe scored the opener for a disjointed PSG, it was no true reflection of the game, with City controlling the fixture and Pochettino having to deal with Messi, Neymar and Mbappe often leaving their seven outfield teammates to do the bulk of the defensive duties.

That defeat suggested that Pochettino had yet to get to grips with his stellar squad or the unique challenges of having to turn it into a team. Madrid will pose PSG the same kind of problems that City did in November, so Pochettino has to find a way to make his players step up.

But while the expectation is that PSG may falter against Madrid and leave Pochettino waiting for the inevitable nudge towards the exit door, the whole picture would change if they can manage to knock the Spanish giants out.

If that happens and PSG gain momentum, a move to United may begin to lose its appeal for Pochettino, as success in the Champions League may also open doors to better opportunities for the 49-year-old. So there is plenty at stake for Pochettino, PSG and United over the next 180 minutes against Madrid.