The Egyptian giants suspects that some players might be using performance-enhancing drugs.
Zamalek are set to make an official request to the Egyptian FA to administer doping tests as they suspect that some Egyptian Premier League players might be using performance-enhancing drugs.
"The Zamalek management, in association with the board, will request a precise assessment from the FA for doping tests in the league," football director Ibrahim Hassan told the club's official website.
"We have the right to make this request because the following weeks will witness hectic competition and we hope it would be a fair."
Zamalek, who won 1-0 at Ghazl Mahalla on Monday, are six points adrift of leaders Ahli but the latter have a game in hand.
The defending champions came back from behind to beat Petrojet 2-1 in Cairo on Monday.
Following Ahli's controversial victory over ENPPI last week, Zamalek issued a statement protesting over their rivals' victory and asking the FA to interfere and assess the conduct of league matches by referees.
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