Jurgen Klopp says Naby Keita will be out for around two months after he was injured in Liverpool's defeat at Barcelona on Wednesday night.
Keita started for Liverpool during the 3-0 defeat at the Nou Camp, but sustained an injury in the first half and had to be replaced by Jordan Henderson.
Klopp has confirmed Keita will miss the last few games of the season - as Liverpool continue their chase for glory on two fronts - and also potentially the Africa Cup of Nations in Egypt this summer.
"It was really unlucky - and bad news," said Klopp. "He has a high grade adductor injury. The tendon is ruptured, which keeps him out for at least, I would say, two months.
"Bad news for us, bad news for Guinea as well, because the Africa Cup of Nations is coming up.
"That is how football and life sometimes are, not too nice. But it is very serious and for sure it is not the best moment for him.
"He will not be part of a very interesting part of the season and the Africa Cup of Nations was a big target for him as well.
"So, it is not a good moment but that is the moment you have to help the players. We will try everything we can."
Liverpool face Newcastle on Saturday as they continue their bid to win the Premier League title, before hosting Barcelona in the second leg of their Champions League semi-final on Tuesday, when they will try to launch a stirring comeback.
Liverpool then play Wolves in their last top-flight game of the season next weekend.
Guinea's first match in the Africa Cup of Nations is against Madagascar on June 22.