Sundowns made three changes from their midweek win over Polokwane City, aiming to get a full grip on the MTN 8 title this year.
For Nkosingiphile Gumede, the Arrows keeper was first to make a save, punching Lyle Lakay’s free-kick over the top in the opening minutes.
Abafana Besthende’s first foray on goal came after 24 minutes when Thabo Molefe showed good control before taking a low shot at Kennedy Mweene, which he easily saved.
Out of nowhere, Arrows almost went behind when Gumede at first struggled to bring a back-pass under control before clearing away at the second attempt.
On the half and hour mark, Sibusiso Vilakazi missed the best chance to give Downs the lead as he fired over the top from close range.
Vilakazi soon made amends, blasting home the opener from close range leaving Gumede flat-footed after being set-up by Gaston Sirino and Themba Zwane.
Arrows searched for a way back early on, but Knox Mutizwa’s lethalness upfront wasn’t as clinical as known by many across the league.
After 54 minutes, Downs introduced new signing Andile Jali for Lebogang Maboe, with the lead firmly intact.
Shortly, Sirino nearly made it two when he found himself central to goal, but his shot on the turn failed to find the top-corner, sailing over the post.
Arrows first change happened on 68 minutes when Siboniso Conco made way for Siphelele Magubane, with their tails still hanging between their legs.
A minute later, their cause worsened when Wayne Arendse, in for the injured Ricardo Nascimento, headed in at the far post following a cross from Sirino.
The Brazilians seal a spot in the semi-finals of the season-opening spectacle, hoping to go better than their runners-up berth in 2016.