PSG have become famous for their Champions League collapses, and everything seems to be pointing the wrong way entering this year's last 16.

A similar scene unfolds every year.

A retooled PSG side gears up for a Champions League run. Players are added. A manager is hired. New formations are established, adapted and perfected against the mediocrity of Ligue 1. And then, PSG are eliminated, usually in heartbreaking fashion.

This Champions League plight is more than a curse at this point. By now, it's a routine, a familiar cycle that always comes to the same inevitable end.

And it all seems geared to go wrong once again.

This is probably the best, most complete PSG squad in years. They have a more pragmatic manager who has, at times, drawn the best out of a star-filled squad.

But as PSG prepare to face Bayern Munich in the first leg of their last-16 knockout tie on Tuesday, the warning signs are adding up. From injuries and fatigue to arguments and poor fortune, here's why it could all go wrong again…

(C)Getty ImagesMbappe's Injury

Even though Mbappe made a surprise return to training on Monday morning, his fitness should still be a massive concern for PSG. The star winger injured his hamstring on February 1, with an expected recovery time of three weeks. That he is back within 11 days is good news for manager Christophe Galtier, but also brings concern that he's been rushed.

And what kind of role will Mbappe play? It certainly seems hasty to let him start, but Galtier insisted that Mbappe isn't in the squad just to fill out numbers. A second-half introduction seems likely, but will it be worth risking their star player with a second leg coming up? And with Ligue 1 far from locked up, Galtier has a choice on his hands. An aggravation of his star player's current injury would be an absolute nightmare.

AdvertisementGettyCampos' Rant

There is allegedly trouble in the PSG camp. Sporting director Luis Campos watched the squad he assembled suffer an embarrassing loss against Monaco on Saturday, and reportedly tried to intervene. According to , Neymar, Marquinhos and Campos got into a spat following the defeat, with Campos criticising the team for a lack of effort.

Campos typically doesn't have much influence over such matters, and the fact that the sporting director is trying to meddle in day-to-day affairs with players is an alarm bell for greater dysfunction.

Getty ImagesNeymar's Antics

What to do about Neymar? At his best, the Brazilian is unplayable, and one of the best footballers on the planet. On bad days, he's a liability. This is not to say that PSG should bench Neymar, nor that he is no longer one of the world's best. And he always seems to perform in the big games.

But personal issues seem to be impacting the team's performance at the moment. He and Mbappe have dealt with well-documented tension between them, while Neymar also reportedly had a go at Vitinha and Hugo Ekitike during the loss to Monaco on the weekend.

"It happened, a little discussion, we didn't agree," the Brazilian said in a press conference about the Monaco incident. "It happens to us every day, but I love them all, it's like with my girlfriend. Football is not just love, not just friendship. There is respect but it happens to have discussions. We are not used to losing, when there are defeats, of course it disturbs us. It is part of the process to improve."

Added head coach Galtier: "When there is frustration, it has to come out. I have been leading this way for years. You have to listen to them but they also have to listen to me. There is frustration that breeds anger. We talked, I listened to them, I hope they listened to me too."

There are two sides to every story, and Neymar has tried to paint himself as a player simply raising the level of those around him with a competitive streak. But this isn't his first internal clash. He might need to pick his battles better.

At an unstable moment for the club, stars are supposed to be leaders and maintain calm. Another drama is the opposite of what PSG wanted entering the Bayern Munich showdown.

(C)Getty imagesZiyech's transfer failure

Hakim Ziyech was never going to be the saviour of PSG's season. The winger is a fine player with a sumptuous left foot, and a hero of the Moroccan national team. But he is not the answer to all of PSG's problems.

Still, he seemed primed to be an important piece. The drop off from PSG's usual front three to Carlos Soler and Hugo Ekitike is massive. Ziyech, at the very least, should have softened the fall. But a transfer from Chelsea fell through at the last minute, with the London club failing to sort the correct paperwork before the deadline.

It left PSG without a clear option off the bench, someone who could have perhaps given Messi or Neymar a rest in the weeks leading up to the Bayern tie – or even start the contest until Mbappe is ready to enter the game.