Ahly players celebrate one of their goals against Eastern Company (Photo: the club s official Facebook page)
South African boss Mosimane surprisingly left the club by mutual consent on Monday after a highly-successful 20-month spell, which yielded two back-to-back African Champions League crowns, one Egypt Cup and two Club World Cup bronze medals among other minor accolades.
But Mosimane could not win the Premier League title, which was Ahly's to lose last season, as Zamalek staged a late rally to capture it.
This term, Ahly look determined to wrestle it back and caretaker coach Sami Komsan, who was Mosimane's assistant, delivered on his first task.
A goal from winger Hussein El-Shahat and a penalty from Taher Mohamed Taher gave Ahly a 2-0 half-time lead and Ahmed Abdel-Kader extended their advantage with a third goal 12 minutes into the second half.
Eastern Company substitute Firas Iffia narrowed the gap with 14 minutes remaining but veteran winger Walid Soliman headed home Ahly's fourth in stoppage time to complete the rout.
Ahly lie third in the table with 40 points, three behind Pyramids FC, who played four matches more, and four adrift of leaders Zamalek, who played three games more.
The Red Devils next face Zamalek in a vital Cairo derby on Sunday.
El-Shahat opened the scoring after 25 minutes, running onto a long ball upfield from defender Rami Rabia to break clear and send a delicate chip over the keeper.
Eastern Company looked dangerous on the break but Ahly struck again on 31 minutes, Taher firing a powerful spot-kick into the roof of the net after left-back Mahmoud Wahid was tripped by Saber El-Shimi.
Striker Ahmed Oufa was a constant thorn in Ahly's defence and he almost scored six minutes before the break when he turned past his marker, only to fire wide from a good scoring position.
Early in the second half, he also sent a low shot just wide after cutting past Rabia on the edge of the area.
But any hopes of a comeback were extinguished on 57 minutes when Abdel-Kader ran onto a threaded pass, flummoxed his challenger and drilled a low shot into the far bottom corner.
Both sides had a goal disallowed apiece following VAR reviews before Tunisian winger Iffia pulled one back in the 76th minute, firing a powerful volley home after a ball was sent to him over the top of defence.
But Soliman ensured Ahly's victory one minute into stoppage time when he sent a free header in off the post following an inviting cross from the left.
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