London - Liverpool defender Joel Matip will be out of action for up to six weeks after suffering a fractured collarbone.
Matip was injured in the final minutes of Liverpool's 1-0 win against Napoli in the Champions League at Anfield on Tuesday.
The 27-year-old landed awkwardly following an aerial challenge and is now set to undergo surgery.
"Matip was taken to hospital following the fixture and further assessment deemed an operation is required," a Liverpool statement said.
"Early indications suggest the centre-back is facing a spell of up to six weeks out of action, though that is dependent on how Matip responds to his treatment and rehabilitation programmes."
Cameroon centre-back Matip had started the Reds' last three matches and his injury is blow to Liverpool's hopes of remaining on top of the Premier League.
Jurgen Klopp's side, who sit one point above Manchester City, are already without injured defender Joe Gomez for six weeks after he suffered a leg fracture in last week's win at Burnley.