Mohamed Sissoko was back in the Liverpool starting line-up to face Birmingham just a month after the eye injury against Benfica which had left him blind for 36 hours.
The former Valencia midfielder suffered the injury to his right eye after being caught by the boot of Beto and there were concerns he would — at the very least — not play again this season.
His introduction was one of six changes made by Rafael Benitez from the side which had triumphed 3-1 at Newcastle on Sunday — Stephen Finnan, John Arne Riise, Luis Garcia, Xabi Alonso and Djimi Traore also returning.
Blues boss Steve Bruce made four changes — three of them enforced — from the side beaten 2-0 by Tottenham in Saturday's Premiership game at St Andrews.
Emile Heskey and Nicky Butt were both injured, DJ Campbell was cup-tied and Stan Lazaridis dropped to the bench, meaning in came Mikael Forssell, David Dunn, Marcos Painter and Stephen Clemence as Blues attempted to reach the semi-finals for the first time in 31 years.
Birmingham: Maik Taylor, Melchiot, Cunningham, Martin Taylor, Painter, Pennant, Johnson, Clemence, Clapham, Forssell, Dunn. Subs: Vaesen, Lazaridis, Kilkenny, Bruce, Tebily.
Liverpool: Reina, Finnan, Carragher, Hyypia, Traore, Alonso, Gerrard, Sissoko, Riise, Crouch, Luis Garcia. Subs: Dudek, Kromkamp, Kewell, Cisse, Morientes.
Referee: R Styles (Hampshire)
