Lyon have been dealt a double injury blow with the news that striker Alexandre Lacazette is out for the rest of 2015 and midfielder Mathieu Valbuena is likely to be.
Lyon president Jean-Michel Aulas said after the 2-0 Champions League win at Valencia on Wednesday that he feared that Lacazette, 24, would miss Sunday's Ligue 1 game against Paris Saint-Germain.
On Friday, the club's manager Hubert Fournier said the Ligue 1 Player of the Year would not be fit for any of Lyon's remaining three matches before the winter break.
France international Valbuena, 31, missed the trip to Valencia and also may not play again before 2016.
"Alexandre Lacazette is unavailable until the end of the year with a muscular injury," Fournier told a news conference.
"Mathieu Valbuena will undergo a clinical examination on Monday to find out if there is a chance of seeing him again before the winter break."
Aulas said France international Lacazette, Lyon's top scorer in Ligue 1 with six goals in 15 matches, had suffered some discomfort in his thigh during the move that ended with him scoring the second goal at Valencia.
Lyon are fifth in the table, 19 points behind PSG ahead of their game against the champions in Paris on Sunday.
"PSG have set the bar very high," Fournier said. "There's a huge gap with the other teams in Ligue 1, but we still have hope of putting them in difficulty."