Morena came off the bench in the 81st minute to collect a poorly cleared ball from defender Yasser Ibrahim and fire from inside the box past keeper Mohamed El Shennawi in the dying minutes of the game, leaving Ahly to rue a host of missed chances.

It is Sundowns' first ever victory against the Red Devils in Cairo and their second in their 11-match history following their historic 5-0 win in Pretoria in April 2019.

Sundowns lead Group A with seven points after three games while Ahly are third with a single point after two games as they still have a match in hand against Sudan's Al-Merreikh.

Ahly coach Pitso Mosimane started with his usual 3-4-3 formation, opting to keep playmaker Mohamed "Afsha" Magdi and South African forward Percy Tau, who has just recovered from an injury, on the bench.

Both sides had a cautious approach early on but Ahly soon took control. 

The defending champions, who are eyeing an unprecedented hat-trick of straight Champions League crowns, dominated possession with their trademark passing game and pinned their opponents into their own half.

They had several chances to get in front as Malian midfielder Aliou Dieng fired just wide twice from the edge of the area while attemps by Ali Maaloul and Mohamed Hani were saved by the keeper.

After the break, Ahly were even more dangerous in a one-sided second half, especially after the introduction of Tau and Afsha who provided a much needed flair in the final third.

Tau had a goal disallowed for a marginal offside, Maaloul's volley skimmed the crossbar and Afsha failed to find the back of the net on several occasions, including an effort with the goal gaping that was denied by last-minute tackle from a defender.

At the other end, Sundowns made the most of a single goal-scoring chance, thanks to fine a finish from Morena.

Ahly attacked en masse in an attempt to grab the equaliser but again Tau, Afsha, Hossam Hassan and Hussien El Shahat squandered their chances.

Ahly will play Al-Merreikh on Saturday in their rescheduled game.