India's Shiv Kapur and Romain Wattel of France shot 6-under 66s Thursday to share the early first-round lead at the Perth International.
Australian Brett Rumford and Northern Ireland's Cormac Sharvin were among those two strokes behind after 68s on the Lake Karrinyup Country Club course.
Louis Oosthuizen, the 2010 British Open champion playing for the first time in Australia, shot 70. Defending champion Thorbjorn Olesen of Denmark had a 71.
Oosthuizen started strongly with three birdies in his first six holes, but bogeyed his 11th hole to fade from the leading group in the European and Australasian PGA tour event.
Wattel took advantage of the calm morning conditions — "the greens were soft ...most of the players could attack the pin easily."