Liverpool fly down to Cardiff on Friday evening hoping that Spanish midfielder Xabi Alonso's badly twisted ankle shows no reaction from a second training session.
If Alonso is fit, skipper Steven Gerrard is likely to take a wide right role in midfield. But if the Spanish international fails to make it, Gerrard will play alongside Mohamed Sissoko with Djibril Cisse possibly landing a start on the flanks, with Harry Kewell on the other wing.
Fernando Morientes is likely to partner Peter Crouch up front but boss Rafael Benitez could otherwise chose to play Crouch as a lone striker with five in midfield, allowing Cisse and Kewell onto the flanks and Gerrard in an attacking linking role behind Crouch.
Robbie Fowler is cup-tied while Luis Garcia is serving the final match of a three-game suspension.
Provisional squad: Reina, Finnan, Carragher, Hyypia, Riise, Gerrard, Sissoko, Alonso, Kewell, Crouch, Morientes, Dudek, Kromkamp, Hamann, Cisse, Warnock, Agger, Traore.