Bernd Wiesberger birdied the last hole to take a one-shot lead after the first round of the Nedbank Golf Challenge on Thursday.
Wiesberger broke clear of the pack with a superb approach to No. 18 to set up his birdie, finishing with a 5-under 67 to edge four other players.
Race to Dubai leader Tommy Fleetwood (73), who can win the season title with a victory at Gary Player Country Club, was six shots off the pace at the penultimate tournament of the season.
Julian Suri, Scott Jamieson, Victor Dubuisson and Brandon Grace (all 68) were a shot behind Wiesberger, who won his fourth European Tour title in China in April.
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Defending champion Alex Noren (69) was in a group of four players another shot back, alongside Charl Schwartzel, Hideto Tanihara and Graeme Storm.
Wiesberger made his move on the back nine with three straight birdies on Nos. 10-12 and another two on Nos. 14 and 16 before finishing with the birdie that gave him the outright lead. That was the last of eight birdies on the day for the Austrian.
Fleetwood has won twice this season on the way to the top of the Race to Dubai standings but he couldn't find his best form on Thursday. Fleetwood made three bogeys and two birdies to leave himself plenty of work to do to win the European title ahead of the season-ending Tour Championship in Dubai.
Noren made eagle at No. 10 and started his defense strongly a year after a sensational final round won him the Nedbank title.
Grace and Schwartzel are well-placed for a title challenge. South Africa hasn't had a home winner at the Nedbank since Trevor Immelman's triumph a decade ago.