Despite the spirited challenges from France’s Alexander Levy and Australia’s Jason Scrivener, Oosthuizen kept his composure to win the A$1.75 million event by one shot at the Lake Karrinyup Country Club.
Levy signed off with a 66 to take second place while Scrivener took the outright third position with his 274 total at the Perth showpiece which saw the return of the best players from the Asian Tour to Australia after seven years.
Singapore’s Mardan Mamat emerged as the leading player from the Asian Tour after he carded a 71 to take sole possession of eighth place with his 278 total.
Victory was especially sweet for Oosthuizen as his win marked his return to the winner’s circle after two years. The 2010 Open Championship winner was also making his first ever professional appearance in Australia.
“It's been two years since I won, so it's great to be back in the winning circle. And to do it here in Perth is really special. It's important to know that you can still win events, and not get too far from winning tournaments or too long from winning tournaments. This will be great for my season going forward,” said Oosthuizen.
The South African, who came into the week as the highest ranked player at world number 21, stumbled with an early bogey on the second hole.
He then saw his overnight three-shot advantage quickly wiped out when Scrivener carded his third birdie on seven to briefly share the lead.
The South African however responded immediately with two birdies on seven and eight to get back to the front and cruised home with an outward 36 despite making a bogey at the last.
“I don't change my game plan. I do what I think is best with each shot, where I give myself the best birdie opportunity. You get nervous, but you feed off that. It's great to be nervous with three holes to go in a tournament because it means you're up there somewhere.
“You've got a chance of winning it. That's what we do all the hard work for. To try and get into that position and it's a great feeling to be able to do that and win a tournament,” said Oosthuizen.
Scrivener, who had the local crowd cheering him on, conceded his title chances were effectively lost after marking his card with a pair of bogeys on nine and 10.
“Those soft bogeys on 9 and 10 really killed my momentum. Once I made those bogeys, I kind of knew my chances of winning were gone,” said the Australian.
Leading scores after round 4 of the ISPS HANDA PERTH INTERNATIONAL being played at the par 72, 6531 Metres Lake Karrinyup GC course (am - denotes amateur):
272 - Louis Oosthuizen (RSA) 70-64-67-71.
273 - Alexander Levy (FRA) 70-67-70-66.
274 - Jason Scrivener (AUS) 69-67-69-69.
275 - Gregory Bourdy (FRA) 73-71-65-66, Peter Uihlein (USA) 65-68-71-71.
276 - Romain Wattel (FRA) 66-73-65-72.
277 - Brett Rumford (AUS) 68-65-73-71.
278 - Mardan Mamat (SIN) 69-69-69-71.
279 - David Lipsky (USA) 72-67-72-68, Julien Quesne (FRA) 73-69-69-68, Magnus A Carlsson (SWE) 68-71-71-69, Benjamin Hebert (FRA) 70-70-68-71, Peter Senior (AUS) 69-73-66-71, Mikko Korhonen (FIN) 71-70-66-72.
280 - Wade Ormsby (AUS) 69-73-70-68, Nick Cullen (AUS) 68-76-67-69, Robert Dinwiddie (ENG) 70-71-69-70, Masahiro Kawamura (JPN) 70-72-68-70, Andrew Johnston (ENG) 70-71-68-71, David Drysdale (SCO) 69-70-69-72, Marcus Fraser (AUS) 69-73-65-73.
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