Al Ahly announced that head coach Jess Thorup had been taken to hospital after suffering a sudden health issue ahead of the club's upcoming meeting with Al Masry.
The initial statement focused on the coach being moved for medical checks, without offering extended medical details or confirming how long he could be away from the team.
The development leaves Al Ahly's assistants with added responsibility at a delicate stage of the season, with the match carrying major technical and competitive importance.