Sergio Garcia made two birdies in his first four holes to extend his lead to three shots on day three of the Nedbank Golf Challenge hosted by Gary Player.
The Spaniard made two late bogeys on Friday to see his advantage cut to just one but re-established his cushion in fine style to get to 11 under at the seventh Rolex Series event of the season.
Local favourite Louis Oosthuizen was eight under with Finn Mikko Korhonen - the third member of that final group - five shots off the lead at Gary Player Country Club
Two-time winner of this event Lee Westwood and Ireland's Shane Lowry were then at five under, a shot clear of Belgian Thomas Detry and England's Aaron Rai.
There was some early movement as Rai and Dylan Frittelli put approaches inside ten feet for opening birdies and Lowry holed a monster on the second to also get to five under.
But Frittelli made a double-bogey on the second and Rai dropped a shot on the third and, with little pressure coming from behind him, Garcia put his foot down.
The 2017 Masters Tournament winner got on the green at the par-five second in two and made his birdie before he hit an approach to three feet on the third and extended his lead to three shots.
He then made an excellent par on the fourth after finding a horrible stance off the tee on the par three.
Korhonen made an excellent par save on the second after finding trouble off the tee and needing to play a smart up-and-down, while Oosthuizen made four pars with the minimum of fuss.
Westwood registered a first birdie of the day on the sixth to join Lowry, while Detry had a single gain on the third.
Nicolas Colsaerts turned in 33 and he was alongside Ross Fisher, Darren Fichardt, Li Haotong and Matt Wallace at three under.
