Mahmoud 'Kahraba' Abdel-Moneim put Ahly in the lead in the 66th minute with a header from inside the box, capitalizing on Emam Ashour's impressive setup.
Hussien El-Shahat extended Ahly's advantage in the 75th minute with a brilliant finish from close range.
Kahraba initially struck the ball, but Medeama goalie Felix Kyei made a remarkable save, only for El-Shahat to follow up and double the hosts' lead.
Substitute Salah Mohsen sealed the victory for Ahly just before full-time, heading in a precise assist from talented midfielder Mohamed 'Afsha' Magdi from the right wing.
With the win, Ahly now sit at the top of Group D with three points, level with Algeria's Chabab Belouizdad, who defeated Young Africans of Tanzania on Friday.
fruitful tactical moves
Ahly displayed high motivation from the start, capitalizing on their home advantage.
They were denied by the crossbar twice in the third minute, with Emam Ashour and Mahmoud 'Kahraba' Abdel-Moneim both coming close.
Throughout the first half, the Red Devils maintained pressure and created more scoring opportunities, but the half ended in a goalless draw.
In a tactical move, Swiss coach Marcel Koller introduced talented South African winger Percy Tau and midfielder Mohamed 'Afsha' Magdi as substitutes, replacing Karim Fouad and Alio Dieng, respectively, ten minutes into the second half.
This change proved fruitful as Ahly found the back of the net twice and secured the victory.
Koller made two more substitutions, bringing on Salah Mohsen and Taher Mohamed Taher for Kahraba and El-Shahat, respectively.
Despite Medeama's attempts to rely on counterattacks, as they enter the CAF Champions League group stage for the first time, Ahly's experienced squad ensured victory.
Following their record-setting 11th CAF Champions League title win last season, the Red Devils are determined to extend their reign.
Ahly's next challenge in the group stage will be against Young Africans in Tanzania on 2 December.
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