The petroleum side are second in the league table with 35 points, five behind leaders Ahli who played a game more.
A victory over Zamalek, who lie fifth on 30 points, will help them close to within two points of the Red Devils.
"It's a great chance for us to mount pressure on Ahli," Mokhtar, who steered Petrojet to Premier League promotion in 2006, told FilGoal.com on Friday.
"If we beat Ahli, it will be as if we gained six points instead of three. We will also go clear of Zamalek and Ismaili in second place."
Petrojet, who defeated Zamalek 2-1 in the away fixture last year, usually excel in the first half of the season before beginning to falter at the halfway stage.
However, Mokhtar said more than once his side were determined to fight Ahli all the way this season.
"There will be special rewards for the players if we beat Zamalek on Sunday," Mokhtar added.