Zamalek slumped to their first season defeat on Monday when they lost 1-0 to promoted side Nogoum FC at Petrosports stadium.
Veteran striker Salah Amin scored the winner in the 27th minute, giving his side their first ever league win.
The Whites dominated possession throughout the game but failed to create any threat in the final third against a well organized and solid Nogoum's defense.
Coach Christian Gross kept his regular squad but he was forced to introduce Tunisian international midfielder Ferjani Sassi after 24 minutes at the expense of injured central midfielder Mahmoud Abdel-Aziz.
Two minutes later the Cairo giants were stunned by Salah Amin's goal that put the visitors ahead.
Amin intercepted a long pass on the edge of the back to brilliantly turn around easing past defender Mahmoud Hamdi to strike at the low corner. The former Gaish and Entag El-Harbi striker has netted his sixth career goal against Zamalek.
The hosts failed to create a proper reaction and were far too easily contained by their visitors.
The second half saw some improvement in Zamalek's offensive performance as Youssef Ibrahim and Congolese striker Kabongo Kasongo squandered easy chances from inside the box.
Zamalek attacked en masse leaving acres of spaces at the back. Amin could have killed the game as he latched onto a long ball behind the defense, beat the on-rushing keeper but his long range shot hit the side-netting.
Zamalek fall to the fifth place in the league table with seven points, three behind leaders Ahly while Nogoum advanced to the 11th place with five points.
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