The reigning African champions are chasing a record-extending 13th title, but must first overcome the South African top-flight side, who are seeking a second title following their sole triumph in 2016.
To reach this stage, the Egyptians defeated Sudanese side Al Hilal in a hard-fought quarter-final, while Sundowns overcame a scare from Tunisian club Esperance.
While Mostafa anticipates a tough encounter, he warns that his former team must not take the Brazilians for granted, emphasizing that their performance in the quarter-finals should serve as a reminder of what they are capable of on their best day.
“Mamelodi Sundowns are a strong team with many experienced players. They’ve proven in this CAF Champions League season that they can win anywhere, so we must take them seriously,” Mostafa told Flashscore.
“In their last match against Esperance, they completely dominated the game, showcasing their strength and resilience. Securing an away draw against a strong Tunisian side will undoubtedly serve as a significant morale booster for them as they prepare to face us.
“The match will be tough because a lot is at stake, but I believe we have a team capable of getting the job done. They are hosting the first leg, which gives us a slight advantage. Football today is unpredictable, and that’s why we must be at our best.”
The Al Ahly–Mamelodi Sundowns rivalry has become a major CAF Champions League storyline, with the South Africans enjoying the upper hand in recent years.
In their last four CAF Champions League meetings, Mamelodi Sundowns have claimed three victories, while one ended in a draw.
He continued: "Al Ahly are aware of this, and there must be no room for error. Based on the stats you mentioned, it’s easy to write us off, but every match is different. Although it's a semi-final, we must approach it like a final.
"We can rely on our top scorers, Emam Ashour and Hussein El Shahat, to deliver the goals, but every department needs to be effective.
"That collective effort will give us the edge. Representing Africa at the FIFA Club World Cup would be a great honour and source of pride."
Meanwhile, Mamelodi Sundowns coach Miguel Cardoso acknowledged the quality within Al Ahly’s squad but maintained that the Egyptian giants are beatable, expressing confidence in his team's ability to rise to the occasion.
“We know that Al Ahly have won many Champions League trophies in the last seven or eight years,” he told club website.
“Last year, unfortunately, I lost a final against them. But I think it is possible to beat them.
“We need to play two very complete and strong games, focusing on the details for sure. We need to be strong and prepare ourselves in the best way.
“The game against Al Ahly is not that far away, but we still have a Nedbank Cup semi-final to play, and that should be our focus now. We will then think about the Al Ahly game.”
On the other hand, Al Ahly manager Marcel Koller expressed his ambition to guide the Egyptian giants to the CAF Champions League final, stating that clinching a third consecutive title would be a historic achievement for the club.
"We faced Sundowns in many matches, and our goal was to qualify for the final," he told El Rayada.
"Sundowns have the motivation to win, and Al Ahly is capable of winning the title. The team's performance wasn't the best,” he told El Rayada.
"All possibilities are open to Sundowns. The matches will be difficult, and we want to win the third consecutive title and achieve a historic achievement.”
