Stenson -- who last tasted victory at the 2007 WGC Accenture Match Play Championship -- didn't relinquish the lead over the final three rounds of the event at the Serengeti Golf & Wildlife Estate, finishing with 1-under-par 71 Sunday.
It was the Swede's the seventh career win on the European Tour.
George Coetzee -- who also managed a 71 after setting a course record in Saturday's Round 3 with a 63 -- ended at 14-under to finish second.
Charl Schwartzel fired a 67, ending with sole possession of fifth at 11-under.
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UPI Sports Results for September 19, 2014