Marc Leishman opened up a two-shot lead at the turn as the Nedbank Golf Challenge moved into its closing stages at Gary Player Country Club.
The Australian came into the final day with a one-shot advantage and turned in a one under par 35 to get to 15 under in Sun City.
Closest rival Henrik Stenson played his first nine holes in 36 strokes and was five shots clear of Robert Streb as a straight shoot-out between the leading pair developed in South Africa.
A win for Leishman would see him become the second Australian winner of the Nedbank Golf Challenge and the second Australian winner of the day on The European Tour after Nathan Holman's triumph at the Australian PGA Championship.
It would also be his first win on The European Tour but he will have to keep Stenson at bay as the 39 year old searches for his tenth win.
Leishman and Stenson both looked to be in trouble on the first but the Swede did well to make par after sending his tee shot right while Leishman holed a testing putt from off the fringe.
Jaco Van Zyl had dropped a shot on the first but recovered with a brilliant approach on the next to secure his second eagle of the week and get to 11 under par - having picked up six shots over the week on the second.
Stenson was left off the tee on the third and had to lay up, resulting in a dropped shot, while Leishman also gave one back after finding the sand with his second shot.
Pars followed at the fourth and fifth for the leading group but when Van Zyl put his tee shot on the fifth left and made a double-bogey, it looked like developing into a two-horse race.
Stenson found the sand on the seventh to drop a shot and when Leishman made a testing ten-footer for birdie on the par three, the lead was three shots.
But the World Number Seven is made of stern stuff and he holed a 15-foot putt on the eighth for a birdie while Leishman could only make par after putting his second shot in the bunker.
Both of the leading duo then made birdies on the par five ninth as Van Zyl recorded a second consecutive bogey to effectively end his chances of victory.
Streb was one over for his round to sit at eight under after ten holes, a shot clear of Branden Grace, Thongchai Jaidee, Louis Oosthuizen and Van Zyl.
