Sibusiso Vilakazi made a return to the starting line-up, as Ricardo Nascimento maintained his spot in defence. For SuperSport, Grant Kekana and Sipho Mbule earned a recall to the line-up.
United asked the earlier questions seconds from kick off as Thamsanqa Gabuza got goal-side to volley at Denis Onyango from the far side, but the Sundowns shot-stopper dealt with the effort rather comfortably.
Vilakazi capped his return to the starting line-up with the opener as he ran in at the back post to slide home Thapelo Morena's low cross on 25 minutes.
Morena's pace down the right continued to unsettle the visitors, as he played an inviting ball to Mosa Lebusa six minutes later, but the former Ajax Cape Town man failed to connect .
Vilakazi played in Gaston Sirino for a shot from the edge of the six-yard area 36 minutes gone, but the Uruguayan's effort flew wide of target.
United made a change after halftime as Kaitano Tembo introduced Thathayaone Ditlhokwe for Siyabonga Nhlapo.
Sundowns went close to adding a second goal after 61 minutes, but Sirino sent his curling effort from the right over the top corner with the defence backing off.
A horrific injury to Morena, who landed awkwardly on the near side, brought his evening to a close as he went stretchered off for Lebohang Maboe following the 71st minute.
Themba Zwane got behind the defence for a one-on-one with SuperSport goalkeeper Ronwen Williams, who rushed off his line to thwart the Bafana Bafana international a minute later.
A few chances went the way of either side in the latter stages, but Masandawana reigned victors in the end.
Sundowns: Onyango, Ngcongca, Lebusa, Nascimento, Kekana, Madisha, Jali, Zwane, Morena, Sirino, Vilakazi.
Subs: Mweene, Mkhulise, Mabunda, Lakay, Maboe, Meza, Arendse.
SuperSport: Williams, Bhasera, Daniels, Kekana, Nhlapo, Mokoena, Furman, Mbule, Mahachi, Gabuza, Grobler
Subs: Pule, Ditlhokwe, Fleurs, Donn, Waiswa, Modiba, Lungu.