Torres, Liverpool's leading goalscorer this season, pulled up after 23 minutes of Spain's friendly against France on Wednesday with what seemed to be a hamstring injury.
"The news we have on Torres is that it is a hamstring injury," Benitez said.
"I need to talk to the doctor but I think he will miss this game. Normally it is a week when a player goes off like this. It is a big problem for us."
Liverpool are fifth in the table, 11 points behind third-placed Chelsea.