Johannesburg - Louis Oosthuizen ended a 33-month winless run by lifting the South African Open trophy for the first time on Sunday after a six-shot victory at Randpark Golf Club in Johannesburg.
The 2010 Open champion last triumphed on the European Tour in 2016 when he won the Perth International in western Australia.
The 36-year-old South African closed with a four-under-par 67, shrugging off a poor start to eagle 14 and finish well clear of runner-up Romain Langasque from France.
Schedule clashes meant Oosthuizen was playing in the South African Open for the first time since 2010 and he wept after clinching an ultimately comfortable victory.
"This is a very special victory for me as I become only the sixth golfer to win the two oldest national golf championships, the British Open and the South African Open."
Fellow South Africans Ernie Els, Bobby Locke and Gary Player, Swede Henrik Stenson and New Zealander Bob Charles previously achieved the 'double'.
"I did not start well today, scrambling a par at one and dropping shots at two and three before recovering with four birdies to turn two under for the round," said Oosthuizen.
"For the second successive round I struggled off the tee early on and had to bite the bullet before coming good as the round progressed.
"While realising that I was building a good lead, it was not until 14 that I could relax a little bit.
"My nine-iron second at that par-five hole was a perfect shot, leaving me with a short putt for an eagle."
Oosthuizen opened with a 62 for the first-round lead, but trailed fellow South African Charl Schwartzel by two shots at the halfway mark having carded a 70.
A third-round 67 gave him a three-stroke advantage and the expected final-round challenges from Schwartzel and in-form Matt Wallace of England never materialised.
Instead, Langasque, who trailed Oosthuizen by seven shots after three rounds, fired a five-under 66 that included an eagle and five birdies to surge into second spot.
Major winner Schwartzel closed with a 72 to share third place with compatriots Thomas Aiken (67) and Bruce Easton (66) and Oliver Wilson (67) from England.
Meanwhile, Langasque, South Africa's Charl Schwartzel and England's Oliver Wilson secured the three 2019 Open Championship spots.
Next week the European Tour move to Leopard Creek for the Alfred Dunhill Championship from December 13-16.
Leading final round scores in the South African Open at Randpark Golf Club in Johannesburg on Sunday (par-71, RSA unless noted):
266 - Louis Oosthuizen 62-70-67-67
272 - Romain Langasque (FRA) 69-68-69-66
274 - Thomas Aiken 67-68-72-67, Bruce Easton 68-69-71-66, Charl Schwartzel 67-63-72-72, Oliver Wilson (ENG) 73-66-68-67
275 - Yikeun Chang (KOR) 70-65-72-68, Branden Grace 66-68-71-70, Jbe Kruger 66-67-72-70, Anthony Michael 67-71-69-68, Madalitso Muthiya (ZAM) 63-68-71-73, Haydn Porteous 68-70-68-69, Brandon Stone 71-67-71-66, Jeff Winther (DEN) 68-69-68-70
276 - Ernie Els 66-71-68-71, Robert McIntyre (SCO) 70-67-68-71, Kurt Kitayama (USA) 63-69-74-70, Zander Lombard 64-68-74-70, Tapio Pulkkanen (FIN) 69-69-68-70, Matt Wallace (ENG) 65-69-68-74