COOLUM, Australia, Dec 13, 2012 (AFP) - Popovic, teeing off at the 10th, birdied his first four holes, bogeyed the sixth then strung together five consecutive birdies on the par-72 Palmer Coolum Resort course to top the leaderboard at the OneAsia co-sanctioned US$1.25 million tournament.
He leads compatriot Scott Strange by two shots, with former US Open champion Geoff Ogilvy a shot further back on five under, alongside China's Zhang Xin Jun and Singapore's Choo Tze-Huang.
Popovic, 26, won the Australian qualifying school late last year but took time off from golf after his father became seriously ill with cancer.
However, his father urged him to return to the sport and he tuned up for the PGA with a practice round alongside Ogilvy.
"That was some of the best golf that I have ever played in my life," Popovic said.
"There were times that I was even surprising myself at how confident I was with the way I was hitting it."
Zhang, a member of China's national golf squad, said he relished the opportunity to play alongside the leading Australian professionals.
"I played very well today, but actually I'm carrying a bit of an injury and my shoulder was hurting coming into this tournament, but I felt very relaxed out there," he said.
"These last two weeks have given us the opportunity to play against the best Australian players, like Adam Scott, but also international stars like Justin Rose.
"I missed the cut (at the Australian Open) last week, but I went to the course at the weekend to watch Tom Watson play.
"This is a great opportunity for young Asian players to learn from the Western players and competing with them can only help to improve our game."
Choo also missed the cut at the Australian Open in Sydney but said he felt more at home at Coolum this week.
"I grew up on tree-lined courses, so I like courses where it is easier to pick a target and just swing it," he said.
"Last week I struggled with my aim, trying to swing the club on line, but here it's much better.
"The greens are also a bit more similar to back home. The speed is good, not too quick, but receptive."
Veteran Australian Peter Senior, who became the oldest Australian Open champion at The Lakes last week, kept alive his hopes of an historic "double-double" of winning the Open and PGA in the same year on two occasions when he fired a four-under-par 68.
The 53-year-old has won at Coolum twice previously and made five birdies and one bogey to be four shots off the pace.
Last year's British Open winner Darren Clarke of Northern Ireland was in joint 19th place after opening with a two-under in a round of four birdies and two bogeys.
South Africa's Rory Sabbatini, a six-time winner on the US PGA Tour, floundered with a four-over 76 to lie in joint 108th place.
Illness forced former world number one Greg Norman to withdraw from the tournament after playing just two holes of his first round.
Norman, 57, made two bogeys before pulling out because of suspected food poisoning.
Scores after the first round of the OneAsia co-sanctioned US$1.25 million Australian PGA at the par-72 Palmer Coolum Resort course on Thursday (Australia unless stated):
64 - Daniel Popovic
66 - Scott Strange
67 - Zhang Xin-Jun (CHN), Choo Tze-Huang (SIN), Geoff Ogilvy
68 - Jason Scrivener, Ryan Haller, Stephen Dartnall, Peter Senior
69 - Brad Kennedy, Aaron Townsend, Bronson La'Cassie, Marc Leishman, Stephen Leaney, Steve Conran, Adam Bland, Josh Geary (NZL), Matthew Griffin
70 - Steven Jones, Terry Pilkadaris, Michael Wright, James Nitties, Peter Fowler, Stuart Appleby, Adam Crawford, Steven Bowditch, Cameron Percy, Nick Flanagan, Darren Clarke (NIR), Leigh McKechnie, Peter Cooke, Gavin Flint, Jason Kang (USA)
Selected scores
71 - Park Hyo-Won (KOR), Rory Hie (INA)
72 - Nick O'Hern, Li Xinyang (CHN), Greg Chalmers
73 - Kim Do-Hoon (KOR), Robert Allenby, John Senden, Garrett Sapp (USA), Cao Yi (CHN)
74 - Pravee Visalkt (THA), Choi Joon-Woo (KOR), Masaya Tomida (JPN), Huang Wen-Yi (CHN)
75 - Chen Jian (CHN), Jin Daxing (CHN)
76 - Rory Sabbatini (RSA)
77 - Park Ju-Hyuk (KOR), Wisut Artjanawat (THA)
78 - Masahiro Kawamura (JPN), Simon Yates (SCO), Park Sung-Hyuk (KOR), He Ze Yu (CHN), Thomas Petersson (SWE), Park Min-Jun (KOR)
79 - Park Sang-Hyun (KOR), Son Joon-Eob (KOR), Choi Seong-Jin (KOR), Tanutchan Puaktes (THA)
80 - Da Quan (CHN)
81 - Will Yanigasawa (USA)
82 - Supravee Phatam (THA)