Coach Martin Lasarte described Ahly's sudden 1-0 loss at DR Congo's Vita Club as "unfair", saying his side were punished for not taking their chances in the African Champions League clash on Saturday.
The Red Devils were undone by a 84th-minute goal from Tuisila Kisinda, whose shot from the edge of the area took a wicked deflection and looped over the keeper and into the net.
Ahly spurned a clear-cut chance to grab the lead early in the second half when they were thwarted by a superb double-save from keeper Nelson Lukong.
They were also let down by some poor touches in the final third as they launched several breakaways.
"We were the better side for long periods. The defeat was unfair," Uruguayan boss Lasarte told the post-match news conference.
"We wasted a number of goal-scoring chances and at the end Vita Club scored to snatch the win."
Despite their second successive defeat in Group D, Ahly remained leaders with seven points, on level with second-placed Vita Club who revived their qualification hopes.
Tanzania's Simba, third with six points, take on Algeria's JS Saoura (five points) in the other group match later in the day.
Ahly, who lost in the final the past two seasons, need to beat Saoura at home in their final group-stage encounter to ensure their progress to the knockout phase.
"Things have become more complicated in the group now," Lasarte added.
"But we will play at home in the final match and we will be looking to win to book our place in the last eight."
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