Red-hot forward Mohamed Sherif broke the hearts of a small Esperance contingent in Tunis, with his second-half goal giving Ahly a precious 1-0 victory in the first leg of the African Champions League semi-final on Saturday.
Just when Esperance abandoned their conservative approach in the second half, Sherif, who has produced some superb displays this season, showcased his poaching skills to exploit the gaps they left and settle the tie in Ahly's favour.
He ran away from his marker to latch onto a through ball from Aliou Dieng and score on the second attempt after his initial shot came back off the post.
Esperance, looking jaded, failed to find a response as Ahly took a giant stride towards reaching the final for a second consecutive season as they chase a record-extending 10th Champions League crown.
The Red Devils also avenged their bitter 3-0 defeat at the same Hammadi Agrebi venue in the Champions League final in 2018. Although they lacked flair on the road, their sturdy defensive display kept Esperance at bay for the majority of the game.
Ahly will host Esperance at Cairo's Al-Salam Stadium in the second leg next Saturday.
The match's kick-off was delayed by an hour as Tunisian security forces clashed with the home fans, firing tear gas in the stands. Only 5,000 supporters were allowed to attend the game due to coronavirus concerns.
Both sides made a cautious approach, appearing unwilling to take any risks in a low-tempo first half that was short on quality and excitement.
Esperance set about exposing the gaps behind Ahly's third-choice right-back Akram Tawfik, who deputized for injured duo Mohamed Hani and Ahmed Ramadan.
But Ahly's conservative formation, which featured three central defenders, ensured Esperance would not find enough spaces to mount threats.
However, the hosts still created the first-half's only genuine goal-scoring opportunity in the 34th minute when Mohamed Ali Ben Romdhane ghosted behind the defence and controlled a floated ball in the area.
He cut inside Moroccan central defender Badr Benoun and attempted to round towering keeper Mohamed El-Shennawi, who stuck out his hand to push the ball away from Ben Romdhane's feet as Ahly breathed a sigh of relief.
Ahly had a goal correctly disallowed for offside a few minutes earlier and created a half-chance when Salah Mohsen ran onto a quickly-taken free-kick from Ali Maaloul, only to see his angled effort smothered by Esperance keeper Moez Ben Cherifia.
The visitors looked livelier in the second half, stepping up a gear after Esperance threw caution to the wind.
Taher Mohamed Taher could have given Ahly a 54th-minute lead when he popped up unmarked at the far post to receive Akram Tawfik's cross with a first-timer that hit the side netting from a good scoring position.
Sherif made amends 13 minutes later and could have added a second in the latter stages when his close-range effort was collected by keeper Moez Ben Cherifia after a corner was flicked into his path.
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