Even after Mokoena's exit, Sundowns continued to search for a second goal to seal the match and came close to doing so via Costa in the 40th minute, but his attempt was blocked for a corner.
Sundowns skipper Themba Zwane was denied by Mayhoub moments before the break after breaking through Pyramids' defence.
The home side always looked dangerous on the counterattack with South African striker Fagrie Lakay and Fiston Mayele, the former Young Africans (Tanzania) marksman, keeping Downs' defence on their toes.
Sundowns found themselves in trouble in the second half, often when they tried to build their play from the back, with Pyramids pressing them high with more numbers as they sought an equaliser.
However, it was again through Sundowns' sheer belief in their playing pattern that they never changed gear despite the pressure of playing away from home. Mokwena's team maintained their possession and passing game, and it helped in managing the game and protecting their slim lead.
Since winning the Champions League for the first and only time in 2016, Sundowns have only failed once, in 2018, to reach the last 16 of Africa's most prestigious interclub competition.
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Sundowns reclaim top spot in Group A via Mokoena’s super strike in Cairo
Teboho Mokoena produced an excellent strike to hand Mamelodi Sundowns a huge advantage in their mission to advance to the quarterfinals of the Caf Champions League as they beat Pyramids FC 1-0 at 30 June Stadium in Cairo on Tuesday night.
However, there was great worry on the Sundowns bench when Bafana Bafana midfield general Mokoena hobbled off the field in the 35th minute and had to be replaced by Bongani Zungu, who did well in his place.
Bafana coach Hugo Broos, who also relies heavily on the Sundowns midfielder, will be hoping the injury is not serious enough to keep Mokoena out of the Africa Cup of Nations in Ivory Coast in January. Broos cannot afford to lose another key player after striker Lebo Mothiba was ruled out of the Nations Cup sustaining an injury playing for French Ligue 1 side Strasbourg on Sunday.
Broos will name his final 23-man squad for the tournament on December 28, and Mokoena and Mothiba had been expected to be among the first names considered.
The win moves the Brazilians to the top of Group A with two more matches to come — away to Mauritanian side FC Nouadhibou in February and at home to Democratic Republic of Congo's TP Mazembe in March.
The Brazilians needed Tuesday's victory. Their 1-0 defeat away to Mazembe and draw at home to Pyramids two weekends ago left all four teams in Group A on four points and Downs far from a comfortable position. An away victory in Egypt has certainly boosted the Brazilians' prospects again.
Mazembe briefly occupied top spot in the group after beating Nouadhibou 2-0 in Lubumbashi earlier on Tuesday.
Both Sundowns and Mazembe are now on seven points, but Rulani Mokwena's side are ahead on goal difference.
Sundowns started well, dominating possession despite the Pyramids packing their midfield and defence. The Pretoria team broke the deadlock in the 17th minute with Brazilian striker Lucas Costa beating a number of Pyramids defenders before laying a good pass to Mokoena, who unleashed a powerful ground shot from just outside the area to beat goalkeeper Ahmed Mayhoub.
Even after Mokoena's exit, Sundowns continued to search for a second goal to seal the match and came close to doing so via Costa in the 40th minute, but his attempt was blocked for a corner.
Sundowns skipper Themba Zwane was denied by Mayhoub moments before the break after breaking through Pyramids' defence.
The home side always looked dangerous on the counterattack with South African striker Fagrie Lakay and Fiston Mayele, the former Young Africans (Tanzania) marksman, keeping Downs' defence on their toes.
Sundowns found themselves in trouble in the second half, often when they tried to build their play from the back, with Pyramids pressing them high with more numbers as they sought an equaliser.
However, it was again through Sundowns' sheer belief in their playing pattern that they never changed gear despite the pressure of playing away from home. Mokwena's team maintained their possession and passing game, and it helped in managing the game and protecting their slim lead.
Since winning the Champions League for the first and only time in 2016, Sundowns have only failed once, in 2018, to reach the last 16 of Africa's most prestigious interclub competition.
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