Miguel Cardoso handed Nuno Santos his first start of the season, and the Portuguese winger made an immediate impact. In the 14th minute, his cross created chaos in the Richards Bay box, allowing Tashreeq Matthews to fire home on the rebound.
The champions quickly doubled their lead when Malibongwe Khoza rose highest to nod in from a corner after Iqraam Rayners had been denied by goalkeeper Zama Otieno.
Richards Bay clawed one back in the 31st minute as Gabadinho Mhango dispossessed Khoza and cleverly chipped Ronwen Williams.
However, Sundowns restored their cushion just before the interval when Khuliso Mudau was brought down in the box, and Rayners calmly dispatched the penalty to make it 3-1.
Matthews capped off a brilliant individual performance in the 62nd minute, seizing on a rebound after Rayners had rattled the crossbar to complete his brace and put the result beyond doubt.
The midfielder's energy and composure stood out as Masandawana dominated the second half to close out the contest.
The win moves Sundowns to 21 points from 10 games, reclaiming top spot on the table.
They sit one point clear of Sekhukhune United, who suffered a setback against Polokwane City earlier in the day, though Sundowns have played a game more.
Durban City rally to overcome Magesi and climb into top three
Elsewhere, Durban City fought back from a goal down to claim a 3–1 victory over Magesi in their Betway Premiership clash at Chatsworth Stadium on Saturday.
The Citizens, winless in their previous two matches, fell behind when Wonderboy Makhubu headed home for Dikwena tsa Meetse on 29 minutes. But Gavin Hunt's side rallied after the break, with Samkelo Maseko levelling on 50 minutes.
Saziso Magawana's fine strike put City ahead in the 77th minute, before Letsie Koapeng sealed the win late on after Elvis Chipezeze parried Maseko's effort.
The result lifted Durban City to third place, edging Polokwane City on goal difference, while John Maduka's Magesi slipped to 13th following a second straight defeat.
Golden Arrows became the first team to book their place in the Carling Knockout quarter-finals after thrashing Chippa United 4-0 at King Zwelithini Stadium on Saturday afternoon.
Mandla Ncikazi has credited Orlando Pirates for playing a significant role in his development as a coach, insisting that maintaining good relationships helped pave the way for his return to Golden Arrows.
Orlando Pirates head coach Abdeslam Ouaddou has challenged his players to believe they can end the club's 31-year wait for a second CAF Champions League title after securing their place in the group stages.
Kaizer Chiefs head coach Fernando Da Cruz believes his side should have secured qualification for the CAF Confederation Cup group stages long before the penalty shootout against Red Arrows.
