Everton will bid to reach the Europa League group stage without two of their major summer signings.
Midfielder Davy Klaassen and striker Sandro Ramirez have not travelled with the squad to Croatia for Thursday's play-off second leg against Hajduk Split.
Everton manager Ronald Koeman confirmed at his prematch news conference that Klaassen is sidelined due to a foot injury, while Sando remains troubled by a heel problem.
"Sandro did not travel and neither has Davy Klaassen, who got a knock on his foot," Koeman said.
"Davy will be out for at least one week, but he will be fit after the international break.