Pablo Larrazabal retained his three-shot leading going into the final day of the Alfred Dunhill Championship.
Seeking his first European Tour win since 2015, the Spaniard carded a two-under round of 70 on Saturday.
That maintained his advantage over first-round leader Wil Besseling, who matched his score, while home hope Branden Grace's 71 meant he slipped to four shots behind Larrazabal.
Zander Lombard and Marcus Armitage sit on five under par in a tie for fourth ahead of Sunday's action, six shots behind the leader.
It was Sweden's Joel Sjoholm who had the best round of the day at Leopard Creek with a 68 and he is one of four players sitting on four under.
Eight birdies in the first 13 holes had Sjoholm flying but he dropped a shot at the 16th and double-bogeyed the last in a blow to his hopes of challenging the leaders.
Leader Larrazabal, whose most recent triumph came at the BMW International Open in June 2015, had five birdies and dropped three shots in a steady effort, though one of his bogeys came on the 17th and denied him the chance to extend his advantage.
He earlier overcame finding the water for one of his other dropped shots at the seventh and goes into round four in a strong position with the field well spread out behind him.