Liverpool boss Arne Slot says Hugo Ekitike's injury "looks really bad" after the France striker was taken off on a stretcher during Tuesday's Champions League loss to Paris St-Germain.
Ekitike went down off the ball 30 minutes into the quarter-final second leg, which the Reds lost 2-0 on the night and 4-0 on aggregate.
He was seen holding his ankle and was visibly in discomfort before being taken off the pitch.
"Hugo looks really bad but it is difficult to say how bad," Slot said after the game.
"Let's see. It doesn't look good, that is clear. I didn't see him at half-time and after the game he was already home. I have not spoken to him yet."
Ekitike is playing his first season at Liverpool after signing last summer from Eintracht Frankfurt and has scored 17 goals in 45 games in all competitions.
A lengthy period of time out for the Frenchman will be a real blow to his hopes of being part of the France squad at this summer's World Cup in North America.
Ekitike's club and international team-mate Ibrahima Konate said this moment will be "very hard" for him.
"I think it is bad," he told Amazon Prime.
"I don't know, I have heard many things, I have no word to talk about that because with the World Cup coming it is very, very hard for him and I send him my prayers."
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