Egyptian giants and record eight-time winners Ahly suffered their worst ever defeat in African competitions after they were outclassed in a stunning 5-0 loss at South Africa's Mamelodi Sundowns on Saturday.
The embarrassing defeat in the first leg of the African Champions League quarter-final almost certainly ends Ahly's bid for their first accolade since 2013.
It also surpassed their 4-0 loss to Nigeria's Enugu Rangers in the CAF Cup, the old version of the Confederation Cup, in 2003 as their biggest ever defeat.
Sundowns, cheered on by a passionate crowd at Lucas Moripe Stadium in Pretoria, went to the locker room two up, thanks to goals from Themba Zwane and Wayne Arendse.
The visitors' disastrous defence was torn to shreds in the second half, with further goals from Ricardo Nascimento (penalty), Gaston Sirino and ex-Ahly forward Phakamani Mahlambi compounding the misery of the Red Devils.
Ahly host the second leg in Suez next weekend, where they would be looking to restore some of their shattered pride.
The stunning reverse in Pretoria will heap pressure on Uruguayan coach Martin Lasarte, whose arrival coincided with a January spending spree that yielded immediate results in the Egyptian Premier League, with Ahly closing to within two points of perennial rivals Zamalek on top.
Ahly were pegged back from the early stages, with Sundowns moving the ball around smoothly and leaving opposing defenders chasing shadows with an intricate passing game.
They deservedly went ahead on 14 minutes when a long ball found Tebogo Langerman unmarked on the left to send an inviting low cross that was turned in by Zwane from close range.
It was a one-way traffic from then on, with Sundowns repeatedly exploiting gaps in a shaky backline to launch a wave after wave of attacks.
Lebohang Maboe was denied by keeper Mohamed El-Shennawi in a one-on-one on 22 minutes but Arendse made amends one later, sneaking in to convert a floated free kick from close range after once again catching the entire backline off-guard.
Ahly's bid to get back into the game was not helped by an injury that hit central defender Saad Samir, who made way for Yasser Ibrahim before coach Lasarte made a second early substitution by introducing playmaker Nasser Maher to add much-needed spark as the team sought to push forward.
But Ahly were still given three let-offs in quick succession, with the woodwork denying Sundowns twice and Sirino volleying over the bar with the goal at his mercy.
Ahly's solitary chance fell to Amr El-Sulaya on the stroke of halftime but he could only send a weak effort into the keeper's hands from six yards out.
Sundowns overwhelmed their helpless opponents after the break and they were awarded a dubious penalty in the 47th minute when El-Shennawi appeared to have felled an opponent, although television replays suggested that there was no contact.
Nascimento sent El-Shennawi the wrong way from the spot and a demoralized Ahly looked to have given up at this point, surrendering possession far too easily and failing to muster a single effort on goal.
Sirino added the fourth in the 62nd minute with a powerful shot from inside the area after the defence failed to intercept a square pass and Mahlambi completed the rout with a sliding effort into an unguarded net following a low cross from the right hand side of the area seven minutes from time.
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