Ahly appeared to have suffered a hangover from their Egyptian Premier League triumph when a howler by under-fire goalkeeper Sherif Ekramy allowed ASEC Mimosas to hand the Red Devils a second successive African Champions League loss on Tuesday.
The 32-year-old guardian let a header slip out of his grasp and Armand Niamke stabbed home with 10 minutes remaining as Ivory Coast's ASEC snatched a 2-1 victory to make up for their opening loss at home to Wydad Casablanca in Group A.
Despite being roared on by their passionate fans at Alexandria's Borg El-Arab Stadium, Ahly fell behind to Yannick Zakris' thumping shot in the first half but towering defender Ahmed Hegazy brought them level early in the second half.
But a late stunner dealt a serious blow to Ahly's hopes of booking a last-four berth, having slumped to another surprise 3-2 defeat at Zambia's ZESCO United earlier this month. They are at the bottom of the group with no points, with ASEC on three.
Morocco's Wydad and ZESCO, who both have three points, meet in the other group match on Wednesday.
Tuesday's defeat marks Ahly's worst start to a group-stage campaign since they suffered two opening defeats in 2002.
Ahly celebrated their ninth Egyptian league title in 10 seasons when they beat Ismaily 2-1 last Saturday, with Dutch coach Martin Jol saying the club would quickly switch their attention to the elite Champions League competition that they won a record eight times.
But they looked rusty and rudderless as ASEC comfortably kept them at bay. The hosts also struggled for creativity in the absence of 19-year-old prodigy Ramadan Sobhi and in-form playmaker Abdallah El-Saied, who are both injured.
Fast counter attacks
ASEC soaked up pressure in the first half and appeared dangerous on the break, exposing gaps in an advanced backline as Ahly's two central midfielders, skipper Hossam Ghaly and veteran Hossam Ashour, were largely outpaced.
At the other end, Ahly often found it difficult to carve out openings, moving the ball around aimlessly as ASEC's defenders were hardly troubled during a timid opening.
The visitors signaled an intention to rely on their fast-faced counter attacks to unsettle Ahly when Striker Youssouf Dao went close with a powerful shot that went just over the crossbar from the edge of the area on 15 minutes.
There was no mistake on the second attempt.
In the 29th minute, Coulibaly Dala laid off the ball to Zakri who created space for himself and unleashed a piledriver that went into the top corner past the despairing of keeper Sherif Ekramy from 20 metres.
Ahly's first real chance came five minutes later when Herve Koffi failed to handle a tame cross but the ASEC keeper redeemed himself quickly to block John Antwi's low shot on the follow-up.
Ashour also forced a superb one-handed save from Koffi with a powerful half-volley while Ghanaian frontman Antwi sent a looping header over the bar just before the halftime whistle.
But Koffi was unable to prevent Ahly from equalising seven minutes into the second half when, under pressure from substitute Amr Gamal, he could only punch an innocuous header from Antwi into the path of Hegazy who volleyed home into an empty net.
A period of sustained Ahly pressure ensued, forcing ASEC to retreat and stopping their breakaways in their tracks.
Antwi's bouncing header went over the bar with the goal at his mercy nine minutes past the hour mark, with Martin Jol replacing him with veteran striker Emad Meteb shortly after.
Meteb is famous for his last-gasp winning goals but it was Niamke who stole the show with a late strike as ASEC left Ahly with a mountain to climb if they are to book one of the two group tickets to the semi final.
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