Ahly wasted a chance to edge closer to the Egyptian league title after Monday's 3-2 loss to bitter rivals Masry on Monday.
Two first-half goals by Moussa Dao and Ahmed Kaboria and a third by Mohamed Mossaad after the break gave the Port Said-based club a comfortable lead.
However, Ahly redeemed themselves to score two late goals while they were denied by the bar three times .
The defeat blew the title race wide open as the Reds are leading the league table with 71 points, five ahead of second-placed and reigning champions Zamalek with three matches to go.
Masry, who boast 52 points, jumped to third place with the title race is still alive for another three matches.
It only took Burkinabe striker Moussa Dao five minutes to give Masry an early lead after a fatal error by Ahly's veteran midfielder Hossam Ghaly.
Ghaly failed to receive a close pass from keeper Ekramy, leaving the ball for Dao who curled the ball past the helpless Ahly goalie.
Ahly players quickly intensified their attacks to restore the balance but seemed to miss the spark and clairvoyant playmaker Abdallah El-Said amid tightened defence from Masry.
Just after the half-hour mark, midfielder Kaboria broke clear after caughting the defenderd napping to double the score for Masry from a powerful shot.
Ahly's active trio Walid Soliman, Moemen Zakareya and Malick Evouna had successive scoring opportunities against Masry goal, but they weren't lucky enough to find the net.
Directly before the break, Ahly were hit by the injury of striker Malick Evouna who made way for John Antwi.
More goals in second half
Ahly started the second half with all guns blazing, seeking to retaliate.
But Ahly defense, who was clearly exposed by the absence of injured centre back Ahmed Hegazy and versatile full back Ahmed Fathi, kept on their howlers allowing forward Mohamed Mossaad to dribble past two defenders and striker in the top corner six minutes from the hour mark.
After 15 minutes, Ahly's in-form youngster Ramadan Sobhi scored from a penalty after Saleh Gomaa's shot was deflected by a Masry defender who handled the ball.
The Cairo side's revival continued in the 87th minute with a second goal by veteran skipper Ghaly who received a clever pass from active teammate Sobhi to strike from inside the box.
Ahly players fought fiercely in the dying minutes searching for the draw but the final whistle came to end their hope for a fifth succesive league win.
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