World No.21 Louis Oosthuizen admits he needs to come up with a better game plan after making an "awkward" start to the Perth International at Lake Karrinyup.
Oosthuizen started strongly with three birdies in his first six holes, but he faded from that point on to finish his opening round at two-under 70.
Frenchman Romain Wattel and Indian Shiv Kapur were the clubhouse leaders at six-under, while Australians Brett Rumford and Scott Arnold were among a group of golfers at four-under.
Oosthuizen left himself with a series of tricky downhill putts, and the tournament favourite wasn't happy with his placements.
"I hit it really well all day, but just found myself on the front nine in awkward spots on the greens," Oosthuizen said.
"I just need to think a bit better around it. I left myself with a few shockers to try and make birdies.
"I found the places on the green you're not supposed to be."
Kapur almost didn't take to the course on Thursday because of a lingering shoulder injury.
The world No.487 injured his right shoulder while lifting his golf bag off a carousel at Singapore airport a few weeks ago, but some treatment just before his opening round eased the pain enough for him to play.
"I was really struggling on the driving range this morning with my shoulder," Kapur said.
"The first few shots that I hit I couldn't really hold the club at the top of my back swing.
"The chiropractor here did a great job to get me fit to play, and I popped a couple of pills.
"Sometimes when you drop expectations and you don't think about your golf swing, it seems to work pretty well."
Frenchman Victor Dubuisson was struggling at three-over after nine holes.