Miguel Reisinho struck first from close range, before Iqraam Rayners converted a penalty to seal Masandawana’s seventh straight league win.
The win moves the defending champions three points clear of Orlando Pirates, who can reclaim pole position on Wednesday when they host Richards Bay.
At the other end of the table, the defeat for Orbit College means they remain second from bottom but remain five points clear of basement dwellers Magesi FC.
Sundowns started the game strongly and were unlucky not to break the deadlock in the first half.
Rayners hit a low shot just wide of the target while Arthur Sales headed over the cross-bar from close-range.
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Orbit College did enough to in the opening period to keep the score goalless at halftime but it was after the interval that Sundowns flexed their muscles.
The Brazilians took just three minutes after the break for the game’s opening goal when Nuno Santos cushioned a header into the path of Reisinho, who swept the ball home.
Less than 10 minutes later Sundowns were awareded a penalty when Khuliso Mudau was fouled by Ramahlwe Mphahlele and Rayners stepped up to convert the spot-kick.
Sundowns will be back in action on Friday in the CAF Champions League when they host Malian outfit Stade Malien for the first leg of their quarterfinal tie.