Paris Saint-Germain celebrated a statement 4-2 victory over Barcelona, but the triumph came at a potentially devastating cost. Khvicha Kvaratskhelia has suffered a torn anterior cruciate ligament in his right knee, with the Georgian winger facing a lengthy spell on the sidelines that could keep him out for the remainder of the season.For Luis Enrique, losing the 25-year-old is a major headache. Kvaratskhelia has become an important part of PSG's attacking machinery, and replacing his pace, dribbling and ability to unsettle defenders will be no easy task.Nightmarish news for PSG: Season over for KhvichaThe Parisian giants are now weighing up their options, with several candidates capable of filling the void left by their No. 7. However, according to Le Parisien, the solution could involve an unexpected tactical experiment.One possibility is to push Nuno Mendes further forward and deploy the Portuguese international on the left wing.Best known for his work as a left-back, Mendes possesses the speed, power and attacking drive that could make him an intriguing option in a more advanced role. He is currently sidelined with an injury himself, however, meaning Luis Enrique would have to wait before testing the idea.Mighty Barca finally defeated by the European kingsThere are more conventional alternatives available, too.Mika Godts, who joined PSG from Ajax during the summer, shares some of Kvaratskhelia's attacking characteristics. The 21-year-old has shown promise, although he still has work to do before he can be expected to shoulder the Georgian's responsibilities.Maghnes Akliouche and Desire Doue are also in contention. Their versatility is particularly valuable to Luis Enrique, who regularly asks his attackers to adapt to different positions and tactical demands.The injury could also open the door for two young prospects: Senny Mayulu, 20, and 19-year-old Quentin Ndjantou.22.00: (1.47) Olympiakos (4.30) Sparta Praha (6.00) According to Le Parisien, both players are highly regarded within the club and are expected to feature in Luis Enrique's rotation. Whether the Spanish coach opts for a like-for-like replacement, a positional reshuffle or a greater role for PSG's youngsters remains to be seen.One thing is certain: losing Kvaratskhelia for several months would force the French giants to rethink their attacking plans at a crucial stage of the campaign. And if Luis Enrique decides that the answer is already within his squad, Nuno Mendes could find himself with a very different job to do.