Final round scores from the Open at the par-72 Old Course in St Andrews, Scotland on Sunday
272 Louis Oosthuizen (South Africa)
279 Lee Westwood (Britain) 280 Rory McIlroy (Britain)
Henrik Stenson (Sweden)
Paul Casey (Britain)
281 Retief Goosen (South Africa)
282 Robert Rock (Britain)
Martin Kaymer (Germany) 283 Alvaro Quiros (Spain)
Luke Donald (Britain)
284 Rickie Fowler
Charl Schwartzel (South Africa)
Ignacio Garrido (Spain)
a-Jin Jeong (South Korea)
Robert Karlsson (Sweden)
Sergio Garcia (Spain)
"It's unbelievable. After the 12th hole it actually become difficult having such a big lead, to keep calm and I'm glad I had those [spare] shots on 18 because I cramped a little with the putter," Oosthuizen told the BBC.
"It's just amazing."
Lee Westwood of England emerged from the pack to finish second with a two under 70, putting him on 279.
Rory McIlroy came in just behind Westwood in joint third. He had led the event after the opening round.
Oosthuizen's playing partner Paul Casey, also of Britain, finished in a tie for third place.
One name not among the top finishers though was Tiger Woods.
The world number one could not pull his game together and finished three-under par to tie for 23rd place.