Mascherano will miss the Champions League tie with Fiorentina on Tuesday, due to a hamstring problem that he picked up during training.
“He was shooting in training and felt something in his hamstring,” said Benitez.
“He went to see the doctor straight away and we found he had a small problem in his hamstring.
“It could be two or three days, but we are not sure.
“It is not a problem because I think we can manage with Stevie or another player. To lose a player like Javier is not good. But we will find solutions, whether it is with Gerrard or someone else.”