David Lipsky's Alfred Dunhill Championship victory sent him to the top of the Race to Dubai Rankings.
The American finished two shots ahead of David Drysdale to end his four-year wait for a second European Tour title. Lipsky, whose previous win was the 2014 Omega European Masters, shot rounds of 70-66-70-68 to win at Leopard Creek Country Club and reach the Rankings summit.
His victory takes him to 472.9 points, 12.9 points clear of England's Aaron Rai, who won the Honma Hong Kong Open presented by Amundi in December.
Drysdale is in third position in the Rankings thanks to his strong showing in South Africa and he is currently 34 points behind Rai.
Louis Oosthuizen, who finished tied for seventh after winning the South African Open the previous week, is in fourth, with Kurt Kitayama, the Afrasia Bank Mauritius Open at Anahita, completing the top five.