The Brazilian has been struggling with a foot injury that has seen him miss the Reds’ last three games and is not yet back in training.
“Bobby, it is not a serious injury, we are all still kind of convinced, but it takes now a little bit longer already than we all thought, especially Bobby thought as well,” Jurgen Klopp said on Friday. “He will not be ready for tomorrow, Bobby. He didn’t train yet. We have to get further information and find a way to get him back.”
Curtis Jones and Kostas Tsimikas both missed Wednesday’s 2-0 victory over Villarreal and the Champions League through illness.
The Greek defender returned to training on Thursday but Jones remains a doubt.
Elsewhere, the German is likely to shuffle his pack again given the tight turnaround from the Villarreal clash.
Diogo Jota, Naby Keita and Joel Matip will all expect to come in, while Joe Gomez could be pushing for involvement should Klopp decide Trent Alexander-Arnold is in need of a rest.
Predicted Liverpool XI: Alisson; Alexander-Arnold, Matip, Van Dijk, Robertson; Fabinho, Keita, Thiago; Diaz, Jota, Salah.