كتب : Hatem Maher
Egypt skipper Hassan picked up a thigh injury during Ahli's goalless draw with arch-rivals Zamalek in the Cairo derby on Thursday.
"We are not sure yet whether Hassan can play against ENPPI," Ahli doctor Ihab Ali told the club's official website.
"We will assess his fitness during the next couple of days."
Versatile midfielder Fathi also faces a race against time to be fit for the crucial encounter after sustaining a knee injury against Zamalek.
Ahli coach Manuel Jose will be keeping his fingers crossed that Hassan and Fathi recover in time for the ENPPI game as he will miss Angolan striker Flavio Amado due to suspension.
Skipper Shadi Mohamed and mercurial midfielder Mohamed Barakat, who missed out on the Cairo derby with injuries, also remain doubtful.
Ahli can not afford to stumble in their remaining four games if they are to ensure winning a fifth consecutive league title.
They lie second in the table on 53 points, one behind rivals and leaders Ismaili, who played a game more.