City were susceptible to the Reds’ fast counter-attacks in last month's Premier League clash, conceding two first half goals and surviving a woodwork strike.
A tweak of formation saw the Blues dominate much of the second period but ultimately still lose 2-1, and Pep says he is still considering his options ahead of the game.
“As for playing five at the back, it depends," said Pep.
"In some games it was good when we did it; some of the others it was not so good.
“It’s a way we can play when we need to. It is nice to have an alternative with the quality we have.
“We use it when we need to adapt and control the counter attacks better and have passes we need at that time - that is the idea."
The City boss admits to enjoying the Carabao Cup and is looking for his third successive triumph in a competition the Club has made our own in recent seasons.
“This competition is nice when we don't pick up injuries for players,” he said,
“It is especially good for those who don't play regularly in the Premier League and if you win, in two or three rounds, you are in the semi-finals.
“If you have had injuries in your squad, you suffer a bit - in this period the players are tired, but after tomorrow we have five days to recover, so it will be good to breathe a bit.
“But it’s a competition we want to win.”
Asked whether his players risk burnout from doing so well in so many competitions, Pep added: “No it would have happened last season when we played so many competitions in the latter stages and the people arrived perfectly,.
“As I say, If there are not many injuries, you can handle it.
“Of course, sometimes you need a long week to rest but it is what it is - I’m not worried but we will see - we did it last season and we can do it again.”