Bill Haas bogeyed two of his last three holes to slip back into a share of the first-round lead with Nicolas Colsaerts at the Nedbank Golf Challenge in Sun City on Thursday.
In his first Nedbank, the American Haas made five birdies and one bogey to move 4 under par and two clear before slips at 16 and 18.
Haas and Belgium's Colsaerts carded 2-under 70s to lead by one from South Africa's Louis Oosthuizen, Scotland's Paul Lawrie and two-time defending champion Lee Westwood of England.
Westwood had three birdies and two bogeys in his 1-under 71 at the Gary Player Country Club, where he's seeking to become the first player to win three consecutive titles.
Justin Rose dropped shots on three straight holes on the back nine for a 1-over 73.