South African world number seven Ernie Els will have to hold off the challenge from young compatriots Charl Schwartzel and Louis Oosthuizen if he is to secure a fourth Alfred Dunhill Championship title.
Els beat Schwartzel, winner in 2004, and Oosthuizen by three strokes for victory in last year's tournament, which formed part of the 2006 European Tour, shortly after his return from knee surgery.
However, the three-times major winner has suffered from patchy form recently and was fined for throwing his club during last week's Sun City Challenge where he finished fourth, five strokes behind Jim Furyk.
"I'm playing nicely and I'm very happy to be home," said Els, who faces being winless in the calendar year for the first time since 1991.
"I'm just a bit frustrated because last week I played okay, but it could have been a bit better here and there."
Britain's Lee Westwood is the next highest ranked player at number 53 and will be playing at Leopard Creek for the first time.
"It's a fantastic setting. You're right in the middle of nature here. Anything is likely to creep out of the bushes and you have to keep your eye on that."
Westwood only arrived in South Africa on Tuesday after missing his flight and shot a 77 in Wednesday's pro-am round.
"I enjoyed it. It's a good course and it's in fantastic condition. But there are some challenging holes out there and it's really demanding in places. It's a good thinking man's course," Westwood said.