Perth - Former British Open winner Louis Oosthuizen shot a 5-under 67 Saturday to take a three-stroke lead after three rounds of the Perth International.
Oosthuizen, making his first tournament appearance in Australia, had a 54-hole total of 15-under 201 on the Lake Karrinyup Cointry Club course.
American Peter Uihlein (71) and Romain Wattel of France (65) were tied for second, with Australia's Jason Scrivener another stroke back after a 69.
Oosthuizen, who had seven birdies, dropped two shots over his final three holes.
"I lost a bit of concentration on 16, worrying too much on the way about where the pin position was," he said. "It was right on a slope. Those things happen. As long as they don't happen when you are tied for the lead with three shots to go."
Overnight leader Uihlein bogeyed the 18th hole and took six shots on the 135-meter, par-3 12th when he hit his tee shot to the back of the green and struggled to recover before taking two putts to finish.
Australian Brett Rumford was five strokes behind after a 73, while Marcus Fraser, who won last week's European tour event in Malaysia, shot 65 to move up the leaderboard, six behind Oosthuizen.
Fraser was tied with Mikko Korhonen of Finland (66), Canada's Richard Lee (68), Mardan Mamat of Singapore (69) and Alexander Levy of France (70).