Thiago Alcantara will miss Liverpool's games against Norwich and Brentford because of the calf injury he suffered against Crystal Palace.
The Spain international was withdrawn during the second half of Saturday's 3-0 win at Anfield.
While Liverpool are awaiting further scan results, Thiago has been ruled out of Tuesday's Carabao Cup tie at Norwich City and Saturday's Premier League trip to Brentford.
"I can't say now how long it will take but definitely not tomorrow (Tuesday) and not at the weekend," Liverpool assistant manager Pepijn Lijnders said.
"Let's get the scan results back and we have a proper diagnosis. A shame as well because he was taking the game by the hand (against Palace), he was a proper playmaker in my opinion.
"In one week we lose two really influential midfielders, that's the bad thing."
The Carrow Road cup tie also comes too soon for Trent Alexander-Arnold and Robert Firmino.
Alexander-Arnold missed the Crystal Palace game due to illness while Firmino has been absent for the last three matches due to a hamstring injury.
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"Let's start with Trent. Our game basically started at 12pm against Palace; he took responsibility to speak with the doctor," said Lijnders, who confirmed Caoimhín Kelleher will start in goal against Norwich.
"It was not easy because these guys - it says a lot about our group anyway - they want to play everything, [even] if they feel a bit shaky or ill. But he took the responsibility.
"That's Trent, there are no Covid symptoms. We test regardless. He should be fine in a few days but Norwich comes too early.
"Then we have Bobby, who will do parts of team training but also not ready. But progressing well. And Neco (Williams) is progressing well as well. Tomorrow also comes too early."