"If (Steven) Gerrard and (Fernando) Torres are not playing at their best, you hardly see where the goals are coming from," Henchoz said. "They probably need two or three very good players if they want to compete."
The 33-year-old has not been impressed by Benitez's squad rotation policy this season.
"The rotation system sometimes in the league was not the best," said the Swiss speaking at the Liverpool leg of BBC Your Game.
"They drew too many times and if they kept their best XI, they would have won a few more games."