Steven Gerrard will be out for three to four weeks with the hamstring problem sustained on England duty, according to Liverpool's medical team.
The Reds captain will undergo a scan later on Thursday but Dr Peter Brukner, head of sports medicine and sports science, confirmed the midfielder's injury was "significant".
"Steven injured his hamstring. He's just been in for an early assessment here and it certainly looks like a significant hamstring injury," said Brukner.
"He's going to be out for a little while, I'm afraid. I'd imagine it could be three to four weeks."
England have been accused of reneging on an agreement on how long to play Gerrard in Wednesday's 2-1 defeat by France at Wembley.