Liverpool captain Jordan Henderson added to the club's defensive problems after going off injured in the first half of Saturday's Merseyside derby.
He was replaced by the inexperienced Nathaniel Phillips after appearing to sustain a muscle injury.
The England midfielder, 30, was playing in defence with several of the club's first-choice centre-backs injured.
"It's not good. It's how it is," said Reds boss Jurgen Klopp after the 2-0 defeat by Everton.
Henderson joins Virgil van Dijk, Joel Matip, Joe Gomez and Fabinho on Liverpool's injury list.
Matip has been ruled out for the remainder of the season while both Gomez and Van Dijk are also long-term absentees.
