Liverpool captain Jordan Henderson has been ruled out until April as a result of the groin injury he suffered against Everton.
The 30-year-old has undergone surgery and will begin rehabilitation.
The England midfielder was forced off in the first half in Saturday’s 2-0 Merseyside derby defeat to add to the club’s defensive problems.
Henderson joins Virgil van Dijk, Joel Matip, Joe Gomez and Fabinho on Liverpool’s injury list.
The midfielder has been used in defence in recent weeks with Jurgen Klopp without his three main centre-backs.
He will now miss at least five Liverpool games, including a home Premier League game with Chelsea and the second leg of their last-16 Champions League tie with RB Leipzig.
He will also be unavailable for England’s three World Cup qualifiers against San Marino, Albania and Poland in March.
“No specific timescale is being placed upon his return,” said a statement on the club’s website.
“However, the 30-year-old is ruled out initially until after the March international break.”
The international break is scheduled for 24-31 March.