Zamalek center-half Salah Soliman became doubtful for the Cairo derby after sustaining a thigh injury during a warm-up game against Arab Contractors on Tuesday.
Zamalek are already forced to do without defender Hani Saied due to suspension as they only have newly-signed Hamada Tolba and fit-again Mahmoud Fathallah as the only bona fide players in their rearguard.
Soliman, 22, is set have a scan on his foot to reveal the extent of the injury amid concerns that he would miss the
Champions League encounter against Ahli next Sunday.
Meanwhile, striker Amr Zaki has been included in the team's squad for the Ahli game even though the club said he is unfit.
Zamalek are languishing at the bottom of Group B following a 3-2 defeat at Berekum Chelsea a fortnight ago.