Stuttgart midfielder Thomas Hitzlsperger has been ruled out of Wednesday's Champions League clash with Rangers by an injury to his right foot.
The former Aston Villa player, 25, had hoped to play in the opening Group E game at Ibrox, but the Germany international has been told he has no chance of featuring.
Leverkusen opted to leave Hitzlsperger behind in Germany, hoping intense treatment will allow him to face Werder Bremen in the Bundesliga on Saturday.
Turkish midfielder Yildiray Basturk, who played for Bayer Leverkusen at Hampden in the 2002 Champions League final, has been included in Armin Veh's squad.
Basturk is fit again after a calf injury and took part in a full training session on Monday.