Zizo celebrates after scoring Zamalek's goal. Photo: Ahram
Zamalek started the game with early pressure and it paid off as they were awarded a penalty in the 19th minute when defender Mohamed Nasr handled the ball in the area.
Zizo made no mistakes from the penalty spot to grab his 15th goal of the season.
Ismaily came close from the equaliser but were denied by the post twice in quick succession.
Mohamed El Shami was found unmarked at the far post but his header was rejected in the 23rd minute and another powerful shot from Ahmed Madbouly hit the post and went into the corner 6 minutes later.
Zamalek had the chance to extend their lead but keeper Mohamed Fawzi made impressive saves to deny Emam Ashour and Seifeddine Jaziri from close range.
Ismaily upped their game in the second half as the Whites sat back on defence to protect their lead.
The Dervishes created some chances but nothing really came to an end against a compact Zamalek’s defence and an in-form Mohamed Awaad between the sticks.
Zamalek set up a quarter-final meeting with Masry who are coached by Egypt’s iconic striker Hossam Hassan.
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