Forward Raheem Sterling, who missed the midweek league win over Tottenham with a foot injury, has to be assessed while youngster Jordon Ibe is cup-tied.
Provisional squad: Mignolet, Can, Skrtel, Sakho, Markovic, Allen, Henderson, Moreno, Coutinho, Lallana, Sturridge, Jones, Ward, Johnson, Manquillo, Enrique, Borini, Lambert, Balotelli.
Souare joined from Lille last month and has been cleared to play in the game at Selhurst Park but Eagles captain Mile Jedinak remains sidelined with an ankle injury.
Yaya Sanogo (hamstring) and James McArthur (thigh) are also struggling to be fit in time while Shola Ameobi is still regaining fitness and unlikely to feature.
Provisional squad: Speroni, Hennessey, Ward, Kelly, Mariappa, Hangeland, Souare, Dann, Delaney, Bannan, Guedioura, Mutch, McArthur, Ledley, Puncheon, Zaha, Bolasie, Gayle, Sanogo, Chamakh, Campbell, Gayle, Ameobi.