Celtic midfielder Joe Ledley could join James Forrest and Beram Kayal on the sidelines for the Champions League Group H opener against AC Milan.
Ledley travelled to Italy with his team-mates but is a doubt with a groin problem. His Wales team-mate, Adam Matthews, however, has overcome the ankle problem that forced him off against Hearts on Saturday.
Israeli midfielder Nir Biton is in the squad but Forrest (sciatica/illness) and Kayal (groin) are ruled out along with long-term injury victim Steven Mouyokolo (Achilles).
Provisional squad: Forster, Matthews, Lustig, van Dijk, Mulgrew, Ambrose, Izaguirre, Rogic, Pukki, Commons, Brown, Ledley, Samaras, Stokes, Boerrigter, Atajic, McGeouch, Balde, Biton, Zaluska.