Ahly, licking their wounds following their elimination from two continental and regional competitions, failed in their bid to return to winning ways after suffering a stunning late 1-0 defeat by Arab Contractors in the Egyptian Premier League on Tuesday.
In their first game under interim manager Mohamed Youssef, who took over following the sacking of Frenchman Patrice Carteron, Ahly lacked spark and imagination, with the absence of several regulars including Moroccan marksman Walid Azaro taking its toll on the team.
Substitute Ahmed Ali capitalized on a recurring defensive mistake from Malian Salif Coulibaly to fire a low shot home on the turn with eight minutes remaining, heaping more misery on Ahly.
In a matter of two weeks, the ailing Red Devils lost 4-3 on aggregate to Tunisia's Esperance in the African Champions League final before waving goodbye to the Arab Zayed Cup at the last-16 stage at the hands of UAE side Al-Wasl.
With runaway leaders Zamalek chalking up a sixth consecutive league win on Monday, Ahly needed to win their first of a series of rescheduled games to remain in touch with their bitter Cairo rivals.
However, they lost ground after another poor performance to remain at the bottom of the 18-team table with 11 points from seven games, although they will move second should they win their six rescheduled matches.
Contractors, whose recent fine run saw them claim four successive victories, are fifth on 20 points.
Chances were scarce in a dull first half, with Ahly having territorial dominance but struggling to carve out any openings.
Wingers Ahmed El-Sheikh and Nasser Maher were given a rare chance to prove their worth but neither made a notable impact. Egyptian international forward Salah Mohsen was also substituted in the eighth minute after picking up an injury.
Ahly's only chance fell to Maher, whose angled cross-cum-shot on the turn went just wide.
Contractors could have caught Ahly by surprise in a rare attacking attempt early in the second half. Maher lost possession in midfield and Contractors quickly moved the ball forward, with winger Taher Mohamed rattling the crossbar with a blistering shot from the edge of the area.
Ahly then laid siege to Contractors' area, albeit without creating many goal-scoring chances.
The closest they came to scoring was on 72 minutes when Walid Soliman fired a powerful angled shot that struck the upright.
But Contractors had the last word when Ali, with his back to goal, neatly controlled a floated free kick, turned and found the bottom corner with a precise shot after his marker Coulibaly slipped.
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