Four birdies on the back nine saw Welshman Jamie Donaldson maintain his three stroke lead at the Nedbank Golf Challenge with one round to play.
The 38-year-old, chasing his biggest single payday yet at the $6.5-million event, kept up Friday's momentum as he returned a third-round score of 67 for a 16-under-par total of 200.
He might have had a more comfortable lead in search of the $1.25-million first prize, had he not bogeyed the 17th at the Gary Player Country Club in Sun City, South Africa.
"I was in between clubs and it put me in trouble but in the end I came out with a good five. I'm still in a strong position and I've got to go out there tomorrow and play really good golf," he said.
"It's a tough field, a lead of three doesn't mean much among these guys."
Donaldson leads from Thomas Bjorn of Denmark and American Ryan Moore, who are 13-under-par.
Bjorn played one of the best rounds of the day, birdying the 18th for a second successive day to finish with a 66.
Moore followed a second-round 65 with a 67 on Saturday, with five birdies in a bogey-free round.
Spaniard Sergio Garcia and Thongchai Jaidee of Thailand both matched Bjorn's 66 to go 11-under, along with world number three Henrik Stenson of Sweden, who hit a double bogey at the par-five ninth to finish with a 69.
For three-time winner Ernie Els, making a record 18th appearance at the tournament called 'Africa's major', a triple bogey early in his round saw him finish with a 77 for a seven-over total that leaves him tie bottom of the elite 30-man field.