Former Netherlands national team and current England club goalkeeper Boudewijn Zenden may be out of action for up to six weeks due to a knee operation.
The 30-year-old player injured the ligaments in his knee during last Saturday's 1-0 victory against Man City.
Zenden missed most of last season due to a knee injury, but head coach Rafael Benitez says this is not the same problem.
"It is not the same knee, so the decision was made that he will need to undergo surgery. He will be out for four to five weeks," said the specialist from Spain.
The loss of B. Zenden is the latest blow to the struggling Liverpool defense line - Spanish Xabi Alonso and Malian Mohamed Sissoko are also slow to return to the field due to injuries.
The midfield defender adds to the list of injured players in the team, which already includes Chilean Mark Gonzalez, Australian Harry Kewell, Brazilian Fabio Aurelio and Englishman Stephen Warnock.
The experienced Dutchman, who has played for teams such as PSV Eindhoven, Barcelona, Chelsea, and Middlesbrough, has scored 7 goals in 54 appearances for the national team.
Liverpool has secured a spot in the next stage of the UEFA Champions League and is currently in first place in Group C, but the team is struggling in the domestic league: they have collected 21 points in 14 matches and are in 9th place.