United’s win over the Blues came in front of a bumper cup crowd of almost 35,000 people.
Three times the attendance that saw Sunderland lose to Burnley on Tuesday evening.
Benitez said: “I said in the press conference before the game that our fans have been amazing during the whole season and for a replay of the FA Cup, to have 35,000 shows how good they are and how important they are in every game. If we can, we will try to give them something.
“But I will say – I don’t like to lie and I will say we will try to use the squad and go as far as we can, but using the squad because we know that we have so many games in the league that it’s important to have everyone ready and choose the best players for every game without taking risks.”