Claude Puel confident Jack Stephens can fill in for Virgil van Dijk
The England Under-21 international replaced Van Dijk during the second half of Southampton's 3-0 victory over Leicester on Sunday.
It was only the centre-back's sixth appearance for the Saints in all competitions.
Puel's side face the daunting task of travelling to Anfield tonight as they look to preserve their 1-0 lead from the first leg.
Virgil van Dijk picked up an ankle injury against Leicester
Liverpool predicted XI to face Southampton
Tue, January 24, 2017
Express Sport brings you Liverpool's predicted XI to face Southampton in their EFL Cup semi-final second-leg clash
1 of 12
Who will Jurgen Klopp start against Southampton in the EFL Cup?
When asked if the second leg at Anfield would be a good experience for Stephens, the Saints boss said: "If he has to play this game, I think he will play with good spirit and he's a good player.
"He is an England Under-21 international and he knows about these important games. He has the quality and I have full confidence with Jack.
Get Quotes on Home Insurance
"He's a good defender, he's intelligent, he can anticipate the action. Very good technically.
"With the Under-21s, you saw at home (against Italy at St Mary's), it was a good game, he was the best player on the entire pitch.
Jack Stephens has represented England at Under-21s level
"Since the beginning, it is a competition we have played with young players. For example, the last round against Arsenal away, we see the young players get a fantastic result.
"The focus was just on their game and this is just as important. They took confidence, they are upbeat in every training session.
"I think it is not a problem, but for Jack and all of the other players, it's just to think about the game, stay strong together."