Steven Gerrard looks set to miss out when Liverpool take on Derby on Saturday due to his broken toe.
"We'll train again this afternoon, but I spoke to Steven again yesterday and the news was not very positive," Benitez told the Liverpool Echo on Thursday.
"It will be very difficult for him to play on Saturday. The doctor will continue to help him, but maybe it's too early for this weekend."
Voronin backAndriy Voronin is expected to be available, however, after missing Tuesday night's UEFA Champions League clash against Toulouse with a thigh strain.
"Voronin didn't have a big problem, but we decided to be careful against Toulouse.
"We also have Fabio Aurelio and Harry Kewell improving all the time and we hope to have them back in the squad soon."
Jamie Carragher has already been ruled out of the clash having only left hospital on Tuesday following treatment for a broken rib and collapsed lung.