Moussa Djenepo continues his recovery from a hamstring problem which saw him miss last weekend's 3-3 draw at Chelsea.
Everton playmaker James Rodriguez has not been ruled out of the trip to St Mary's Stadium.
The Colombia international sustained significant bruising in last weekend's Merseyside derby, but took part in some training on Friday and manager Carlo Ancelotti remains optimistic.
However, fellow forward Richarlison begins a three-match suspension for his red card against Liverpool, while new signing Ben Godfrey looks set to make his full debut at right-back with Seamus Coleman (hamstring) and Jonjoe Kenny (ankle) both out.
Southampton provisional squad: McCarthy, Walker-Peters, Bertrand, Vestergaard, Bednarek, Romeu, Ward-Prowse, Redmond, Ings, Adams, Armstrong, Forster, Stephens, Valery, Diallo, Long, Obafemi, Tella.
Everton provisional squad: Pickford, Godfrey, Mina, Keane, Digne, Allan, Gomes, Doucoure, Rodriguez, Iwobi, Calvert-Lewin, Olsen, Godfrey, Nkounkou, Delph, Sigurdsson, Davies, Gordon, Bernard.