Darren Clarke blames putting for slump
Louis Oosthuizen continued the dominance of South African players on home soil by successfully defending his Volvo Golf Champions title, while Darren Clarke's five over par 77 undid much of his good work from the opening three days.
After leading the tournament in the earlier stages, the Ulsterman finished tied for 24th place on one over par, while Belfast's Michael Hoey was tied for 29th on four over.
Clarke, who has lost three stones in thanks to a new diet and fitness regime, took 33 putts but it felt like a lot more.
"I think I've missed eight times from inside six feet today," he said, after a promising week reached a frustrating conclusion but was still worth a £33,525 prize.
"I just struggled to read them. I missed everything and then missed the ones coming back."
Clearly still under the weather with a persistent respiratory infection, Hoey picked up £29,920 after a closing 74.
Still, he felt better than caddie Gerry Byrne, who was forced to retire after 10 holes due to severe stomach cramps and was replaced by Hoey's coach Johnny Foster.
Simon Thornton played nicely in the company of "legend" Jose Maria Olazabal, outscoring the Spaniard by two with a 71 which left the Newcastle, Co Down-based player £28,565-the-richer on five over.
Oosthuizen was one shot behind compatriot Branden Grace with two holes to play, but birdied them both to card a closing 68 and win by one shot on 12 under par.
That means all seven European Tour events staged at Durban have now been won by South Africans, while eight of the last 11 tournaments in South Africa have been won by home players.
Oosthuizen has also now started each of the last four calendar years with a victory, this one earning him £421,212.
"It was nerve-wracking but I finished strong and I'm just happy that I got it done," he said.
"It's an awesome start for the year. Confidence-wise it's great," he added.
Dubliner Padraig Harrington finished in a tie for fifth on nine under.