Zamalek had to pay for some sloppy finishing in front of goal to lose 1-0 to Congo's Leopards away from home, despite needing only a draw to book a Confederation Cup semi-final berth with two matches to go.
Striker Tresor Mukendi scored the winner for the hosts in the 61st minute, punishing Zamalek for missing some clear-cut chances – courtesy of some poor finishing from striker Bassem Morsi and newly-signed forward Mahmoud 'Kahraba'.
Former Luzern man Kahraba, in particular, did not enjoy the best of Zamalek debuts having wasted two glorious opportunities with the goal gaping either side of Leopards' goal.
The result meant that South Africa's Orlando Pirates leapfrogged Zamalek into the top of Group B table on goal difference, as both teams are now level on nine points.
Zamalek will now need to take a point from their upcoming two games – a visit to Tunisia's Sfaxien and a home fixture with Orlando Pirates.
A dull affair on a terrible pitch
In a largely uninteresting affair, thanks in part to poor pitch conditions; it was Zamalek who posed real threat on goal after just four minutes.
Egypt striker Bassem Morsi volleyed Mohamed Koffi's long ball from the back towards goal, but his strike went straight into the keeper's hands in what seemed to be a certain opener.
The hosts then replied through Cesaire Gandze 15 minutes later, but the Leopards midfielder blasted high from point-blank range, wasting a sitter for the Congolese side.
But it wasn't the end of Leopards' chances though, with Gandze again threatening from the edge of the box before thumping high two minutes from half-hour mark.
Kahraba, Bassem the culprits
After remaining largely quite throughout the first half, it was Kahraba who signaled the start of Zamalek's wasted chances after the break – missing the target from point-blank range with the goal at his mercy just 10 minutes into the second half.
Mostafa Fathi then struck straight into the keeper hands five minutes later after receiving the ball in space at the edge of the box when he could have done much better.
And Zamalek were punished for their poor finishing, as striker Mukendi managed to cut inside of right-back Hazem Emam to see his shot ricochet off the post before flying into the net.
Egyptian league-winning manager Jesualdo Ferreira then intervened by making a double substitution - introducing summer-returnee Mohamed Ibrahim in place of Omar Gaber, and newly-signed full-back Mohamed Adel Gomaa for wide forward Fathi.
The changes meant that converted left-back Hamada Tolba moved to the opposite side on the right flank with Emam pushed forward as a wide man.
The substitutions, however, didn't deliver the goods and Zamalek continued squandering chances failing to score the all-important equalizer.
Kahraba was again the culprit here after managing to evade several challengers on his way into the box before a terrible strike saw the keeper easily collect the ball.
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