Zamalek's winning streak in the Egyptian League ended on Thursday when the club suffered their first league defeat against Petrojet.
The Group B leaders entered the game eyeing their 11th league win in hopes of realising the longest-ever winning run in a single season in the club's history.
Petrojet, however, dashed Zamalek's hopes with a late goal.
Burkinabe midfielder Mohamed Koffi opened the scoring for Petrojet with a nice header in the 30th minute, while Zamalek striker and fellow Burkinabe Abdoulaye Cisse scored the equaliser eight minutes later.
Substitute Mohamed Ragab scored the winner for the visitors in stoppage time, giving new coach Mokhtar Mokhtar a strong start with the team.
Zamalek coach Jorvan Vieria made a number of changes in his starting line-up, offering the chance to some substitutes to play against Petrojet.
However, midfielders Alexis Mendemo and Islam Awad – who enjoyed their first starting roles this season – failed to provide the needed energy.
After 30 minutes of relative calm, Koffi met a fine corner with a nice header at close range to open the scoring for the visitors.
Zamalek reacted quickly, with in-form Cisse receiving a nice pass from Ahmed Eid Abdel-Malek, skipping the last defender to score at close range.
The Burkinabe striker almost added a second, but his header was denied by Petrojet keeper El-Mahdi Soliman just before the break.
In the second half, Zamalek intensified their efforts to clinch three points. Coach Vieria was forced to depend on his stars, with trio Mohamed Ibrahim, Ahmed Hassan and Mohamed Abdel-Shafi entering in the final 25 minutes – but they failed to make an impact.
A defensive lapse in stoppage time allowed Mohamed Ragab to score the winner after defender Mahmoud Fathalah failed to eject the ball from the area.
Despite Thursday's defeat, Zamalek remain group leaders with 30 points, six clear of second-placed Ismaily, while Petrojet climbed to fifth place with 16 points.
Earlier in the day, ENPPI missed a precious opportunity to close the gap with Group A leaders Ahly after being held to a goalless draw by Smouha.
ENPPI remain second in the group with 23 points, four behind Ahly.
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