File photo of an African Champions League game between Ahly and Mamelodi Sundowns (AFP)
Mosimane, who led Sundowns to a host of titles during a highly-successful eight-year reign before taking charge of Ahly in late 2020, eliminated his former club from the Champions League quarters last season.
Ahly won the first leg 2-0 before holding Sundowns to a 1-1 away draw to advance to the semis. The Red Devils then went on to win a second successive title and a record-extending 10th crown.
They were drawn with each other in Group A this time around, with Ahly hosting Sundowns at Cairo's International Stadium in their first duel.
"The recent wins over Sundowns count for nothing ahead of tomorrow's match. Every game has its own circumstances and we always look forward," Mosimane told the pre-match news conference.
Ahly, who had their opening Group A match against Sudan's Al-Merreikh postponed during their FIFA Club World Cup commitments, kicked off their group-stage campaign with a 0-0 draw away to Al-Merreikh's rivals Al-Hilal last weekend.
They laboured for much of their game in Omdurman, with Mosimane blaming fatigue, the pitch's condition and humidity for the sluggish display.
"Our match against Sundowns will be as difficult as the game against Al-Hilal, but it will be played in better conditions in terms of temperature and the pitch," Mosimane added.
"Sundowns' philosophy has not changed; they still maintain the style that I started with them eight years ago, but there are things and points that they have developed in their game."
Al-Merreikh and Sundowns are joint leaders in the group with four points from two games. Ahly will move level with both if they beat Sundowns.
Ahly welcome back regular goalkeeper Mohamed El-Shennawi after he recovered from a hamstring injury that he sustained at the African Cup of Nations. South African forward Percy Tau is also back after recovering from a muscle injury that kept him out of the Club World Cup.
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