Everton will be without James Rodriguez and Seamus Coleman for the trip to Southampton on Sunday.
Rodriguez was injured following an early foul by Liverpool defender Virgil van Dijk last weekend but played on to help Everton record a 2-2 draw in the Merseyside derby.
“Unfortunately, James had a problem during the game,” Ancelotti said.
“He had a mistimed tackle with Virgil van Dijk at the beginning of the game and I think he will not be available for the game against Southampton."
Jonjoe Kenny returned to training on Tuesday and could replace Coleman - who is expected to miss 'two or three weeks' with 'not a big problem' - while Allan is also available.
Richarlison, however, starts the first game of his three-match suspension after he was dismissed against Liverpool.
“We have to put in other players who have the desire to play,” Ancelotti said.
“We are working this week on this and I think we are going to choose a good line-up for the game against Southampton.
“Alex [Iwobi] is a player who works hard. He is fast and with his quality he can help the team be better in certain situations.
“He [potentially] has an opportunity to play but also we have Bernard and Anthony Gordon.
“We have a lot of opportunities to replace Richarlison and James. We are already moving on."
