Javier Mascherano and Steve Finnan are both out of Liverpool's home game with Newcastle on Saturday.
Mascherano has a muscle injury picked up in Wednesday's 4-0 win over West Ham, while Finnan is still struggling with a hamstring problem.
Mascherano is expected to be fit for Tuesday's Champions League clash with Inter Milan, but there is a greater doubt over Finnan.
Lucas is expected to come into midfield to replace Mascherano.
Daniel Agger is continuing his comeback from a metatarsal injury while Andriy Voronin is now back in training after an ankle problem. But neither are expected to figure against Newcastle.
Newcastle's Joey Barton is unavailable for the game and manager Kevin Keegan is also without the injured trio of Mark Viduka, Emre and Stephen Carr.
Shay Given is in Belgium seeing a groin specialist but Nicky Butt, who limped off against Blackburn last weekend, has been declared fit.
Squads:
Liverpool: Reina, Arbeloa, Carragher, Skrtel, Hyypia, Riise, Aurelio, Babel, Benayoun, Gerrard, Mascherano, Alonso, Torres, Kuyt, Crouch, Lucas, Finnan, Itandje.
Newcastle: Harper, Beye, Enrique, Taylor, Faye, Cacapa, Butt, N'Zogbia, Milner, Duff, Owen, Smith, Martins, Carroll, Edgar, Forster, Geremi.