Liverpool defender Joel Matip will be out for up to six weeks after tests showed he fractured a collarbone in the 1-0 UEFA Champions League win over Napoli.
The centre-back landed awkwardly after an aerial challenge during the closing stages of the crucial Group C victory at Anfield, which sent the Reds into the last 16.
Scans have since shown Matip will need to have an operation and is likely to be sidelined until late January.
"Matip was taken to hospital following the fixture and further assessment deemed an operation is required," Liverpool confirmed in a statement.
"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."
The news is a further blow for Liverpool, who are facing a minor injury crisis in defence.
Joe Gomez is out with a leg fracture sustained against Burnley, while Trent Alexander-Arnold was also hurt during the Napoli game and is a doubt for Monday’s (AEDT) Premier League showdown with Manchester United.