Ahly missed-out a golden chance to close the gap on league leaders Zamalek on Monday after losing 1-0 to Ghazl El-Mahalla to drop more points in this season's title race.
Zamalek were held to a 1-1 draw by Pyramids FC on Sunday, allowing Ahly to reduce the gap to only one point with the latter have two matches on hand.
Ahly remain second in the league table with 37 points, four points behind leaders Zamalek, while Ghazl El-Mahalla advanced to the eighth place with 27 points.
Midfielder Ashraf Sayed scored the winner in the 33rd minute of the game with a screamer from outside the area, giving his side the first win against Ahly since 2009.
Ahly started the game in style with winger Hussein El-Shahat squandered two chances in the opening quarter.
In the fifth minute playmaker Mohamed "Afsha" Magdy released El Shahat on the left hand side of the area but his shot from a tight angle was denied by the keeper.
Ten minutes later a poor clearance from Mahalla defenders allowed him to go clear but his curling shot was also blocked by the keeper.
Following that early threa, the hosts regained their composure and were able to contain Ahly's pressure.
In the 33rd minute, Sayed sent a powerful shot from 25 meters from a free kick that went in the bottom of the net, scoring the only game of the game.
Ahly failed to show the proper response and most of their attempts were blocked by Mahalla defenders and keeper Amr Shaaban who produced a string of fine saves to protect his clean sheet.
Coach Pitso Mosimane introduced veteran winger Walid Soliman and left back Mahmoud Wahid at the expense of Taher Mohamed and Ahmed "Beckham" Ramadan respectively but the duo failed to make the presence felt.
As Ahly attacked en masse they left acres of spaces at the back and Ghazl El Mahalla could have doubled their lead on two occasions in the 63rd minute and the 64th minute respectively but they lacked the final touch.
Ahly's first real threat came in the 73rd minute when striker Mohamed Sherif collected a rebound in the area but his shot went wide.
Mosimane introduced more strikers as Walter Bwalya, Marwan Mohsen and Salah Mohsen came in but they weren't fed enough in the box.
In the dying minutes Salah Mohsen had the chance to level the score as he rose above the defence to meet a cross from Afsha but his header went over the bar.
Ahly who dropped five points in the past two games will have a tough mission on Thursday when they visit Ittihad of Alexandria.
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