Paris Saint-Germain forward Neymar will be out for up to four weeks with an adductor muscle injury and could miss both matches against Barcelona in the round of 16 of the Champions League.
The French champions said Thursday that medical examinations revealed a tear along Neymar's left adductor.
PSG travels to play Barcelona in the first leg on Tuesday. The return leg is in Paris on March 10.
Neymar limped off after being fouled from behind during a French Cup game against Caen on Wednesday.
It is the latest injury in Neymar's stop-start career at PSG.
The Brazil striker has been sidelined for spells with foot, groin, rib and ankle injuries since joining PSG four years ago for a record 222 million euros ($269 million) from Barcelona.
Only last month, Neymar was stretchered off with a left ankle injury sustained in a league game against Lyon.
Two years ago, he missed 10 weeks with a right foot injury. He broke a toe in the same foot a year before, putting his place at the 2018 World Cup in doubt.
PSG is also waiting on winger Angel Di Maria, who could miss next week's game against Barcelona after hurting his thigh playing against Marseille on Sunday.
Goalkeeper Keylor Navas has missed the past four games with bruised ribs and an adductor injury.