From Mbappé and Messi's injury to Neymar controversy, this is the main reason

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

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, its a routine, a familiar cycle that always comes to the same inevitable end.

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, heres why it could all go wrong again...

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 hes been rushed.