Thomas Aiken extended his lead over Len Mattiace during the opening holes of the final round at the Alfred Dunhill Championship in South Africa.
The 25 year old started the day with a one shot advantage but birdies at the second and fourth took him to 20 under par, a two stroke lead after four holes.
American Mattiace was one under for the day and 18 under for the tournament through four holes thanks to a birdie at the second.
Aiken was on course to become the first home winner at Leopard Creek since Ernie Els` triumph three years ago.
It was looking increasingly like a two horse race, with a group of five players on 15 under struggling to catch the last pair out.
South Africans Tyrone Mordt and Richard Sterne and English trio John E Morgan, David Lynn and Robert Rock were all five shots off the lead through five holes.