Contractors, who fielded a full-strength side, took the lead seven minutes before the break when Hamdi Zaki converted a penalty awarded after striker Mamadou Niass was fouled in the area.
Ahly notably improved after the break and deservedly levelled the score on 55 minutes when winger Zeyad Tarek, one of the team's exciting young prospects, sent a glancing header home following an inviting cross from Mohamed Ashraf.
The Red Devils were unlucky not to snatch a win, with midfielder Ammar Hamdi sending a weak penalty into the hands of the keeper and substitute Mohamed Yasser having a goal chalked off for a handball in stoppage time.
A VAR review showed Yasser using his hand to help the ball over the line after Sayed Gharib flicked a cross from Hamdi into his path with the goal gaping.
The draw, Ahly's third in as many games, leaves them fifth in Group B with three points, two behind leaders Ismaily with two matches remaining. Smouha, Gouna and Contractors all have four points.
Winners of the three groups plus the best third-placed side will advance to the semis of the third-tier domestic cup competition, which was introduced for the first time this season.
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