Ahly players celebrate one of their goals (Ahram)
In game that featured three penalties and sublime goals, Ahly prevailed despite wasting a chance to record their biggest ever derby win, having taken their foot off gas in the latter stages as Zamalek spared their blushes with two late goals.
Ahly, who were pipped by Zamalek to the league title last season, went 3-0 up inside the first 25 minutes in a stunning start, thanks to an own goal from keeper Mohamed Abou-Gabal, a penalty from Ali Maaloul and an impressive strike from lone frontman Mohamed Sherif.
Zamalek's Mostafa Fathi made an instant impact off the bench to narrow the gap early in the second half via an unstoppable shot but Aliou Dieng quickly restored Ahly's three-goal cushion with an equally impressive curler.
Maaloul converted another penalty on 65 minutes on the second attempt after his initial spot-kick, which was saved before Sherif followed up to slot home, was ordered re-taken for encroachment.
At this point everything seemed to go Ahly's way and a victory similar to their famous 6-1 derby win in 2002 seemed well on the cards.
But they needlessly retreated into their own half and Zamalek took advantage to give the scoreline a more respectable look, with winger Ahmed Zizo converting an 80th-minute penalty and Moroccan winger Achraf Bencharki drilling home in the final minute.
The scoreline eclipsed Ahly's 4-3 victory over Zamalek in the Egypt Cup final in 2007, which produced seven goals.
Ahly will still be elated with the final result as they moved level on nine points with Pyramids FC, the only other team to bag maximum points from their opening three matches. Zamalek, whose 25-match unbeaten run came to an end, are fifth on six points.
Although Zamalek began the game with intent and high pressing, they were left vulnerable as Ahly's packed five-man midfield found little resistance, with Pitso Mosimane's new-found strategy paying off handsomely.
Burly Malian midfielder Dieng, normally a defensive midfielder, made darting runs at the heart of Zamalek's defence and from one such move Ahly went ahead on 16 minutes.
Dieng's shot from the edge of the area took a wicked deflection off Emam Ashour to loop goalwards, hit the bar and bounce off the chest of the unlucky Abou-Gabal and back into the net.
Zamalek barely had time to recover when a needless challenge by right-back Hamza Mathlouthi, who felled Maaloul after the latter cut past him, awarded Ahly a penalty four minutes later and the Tunisian left-back sent Abou-Gabal the wrong way to double their advantage.
Sherif rubbed salt into Zamalek's wounds on 25 minutes, with central defender Mahmoud Alaa at fault after giving away possession on the edge of the area.
Midfielder Amr El-Sulaya pounced on the loose ball and whipped in a delightful 'rabona' cross, which found Sherif at the far post to steal ahead of Mahmoud El-Wensh and send a sliding effort home after it hit the knee of the poorly-positioned Abou-Gabal.
Talented winger Fathi, who excelled while on loan at Smouha last season, gave Zamalek a glimmer of hope on 51 minutes when his wonderful left-foot shot nestled into the far top corner, with keeper Mohamed El-Shennawi rooted to the spot.
But those hopes were quickly dampened just two minutes later when Dieng curled home after a corner was smartly played into his path on the edge of the area, with Abou-Gabal producing a slow reaction.
Maaloul made it 5-1 with another penalty in the 65th minute after Mathlouthi was once again at fault, his late attempt to clear the ball ending up kicking the chest of El-Sulaya.
A late Zamalek rally saw Zizo fire another spot kick into the top corner after substitute Seifeddine Jaziri was tripped before Bencharki's first- timer found the bottom corner on 90 minutes following a lay-off from playmaker Youssef 'Obama' Ibrahim.
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