Roberto Firmino is facing up to a month on the sidelines for Liverpool.
Firmino suffered a hamstring injury during a second-half cameo for Jurgen Klopp’s side in Wednesday’s Champions League win over Atletico Madrid.
The Brazil international only recently returned to action from a similar issue sustained in a 1-1 draw with Premier League leaders Chelsea in late August.
Klopp confirmed on Friday that Firmino is expected to miss a similar period for the Reds, joining fellow hamstring casualities Naby Keita and James Milner.
He said: “Losing Bobby Firmino is a blow but we’ve known for two or three days it’s a serious injury.
“We are talking about weeks, I don’t know exactly but more than four – which I would consider a serious injury.
“Then we have to see. It is Bobby and he is quick healer.
“It’s just before the international break (so) you think they will be ready again after the international break and you (would) take that.
“But that is not directly (going to happen) at the moment. So not good.”