Ahly defender Mohamed Naguib could miss Sunday's match with Sanfrecce Hiroshima in the Club World Cup due to a back injury.
"Naguib missed Thursday's training session and only did some running on the track," read a statement on the club's official website.
"The defender is suffering from a back muscle problem," the Ahly doctor said.
"The medical staff will race against time to prepare him for the Sanfrecce Hiroshima clash," he added.
The 27-year-old, who joined Ahly from Ittihad El-Shorta last season, is a key figure in the Red Devils' central defence alongside Wael Gomaa.
Coach Hossam El-Badry has other options in Sherif Abdel-Fadil or former Egypt U-23 defenders Rami Rabiea and Saadeddine Samir.
Japanese champions Sanfrecce Hiroshima defeated New Zealand’s Auckland City 1-0 on Thursday.
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