Lyon striker Ada Hegerberg has suffered an anterior cruciate ligament injury in training and is set to miss at least the remainder of this season.
The 2018 Ballon d'Or winner and 2019 BBC Women's Footballer of the Year has ruptured the ACL in her right knee, the French club confirmed on Tuesday.
Hegerberg, 24, said: "This is a setback for me, but I'm going to work through this with all my heart and my energy.
"The best is yet to come. You'll see me soon!"
Lyon and Hegerberg have won the Women's Champions League four times in a row.
They could face Arsenal in this season's semi-finals, if the two sides overcome Bayern Munich and Paris St-Germain in their respective quarter-finals.
Norwegian Hegerberg is the highest scorer in Champions League history and has scored nine times in the competition this season.
Her club are top of the French top flight with a three-point advantage over PSG with eight games remaining, with Hegerberg having netted 14 times in the league this term.
The European champions said in a statement: they will not know when Hegerberg will return until after her operation in the coming days.