Popovic, who won the 2012 Australasian PGA qualifying school, flirted with the course record of 62 at the Palmer Coolum Resort in southern Queensland before settling two shots ahead of compatriot and clubhouse leader Scott Strange.
Former US Open champion Geoff Ogilvy, China's Zhang Xin Jun and Singapore's Choo Tze-huang were further one shot behind at tied third.
Popovic - who played the back nine first - birdied his first four holes and went on to sink five consecutive birdies in the round of his life before revealing his father's battle against cancer.
"It really shook me around a lot. It still sort of does when I think about it," the 26-year-old said.
"But I find a lot of strength in him; how he's fighting that and how he really wants me to push forward with my golf and find happiness through him.
"It is a slow growing cancer but you are unsure of when the actual day will come.
"But he is a strong man and a very stubborn man and I think he'll be here for a little while longer."
On his round, he said: "That was some of the best golf that I have ever played in my life. There were times that I was even surprising myself at how confident I was with the way I was hitting it."
Zhang said: "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.
"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."
Defending champion Greg Chalmers began his title defence with an even-par 72 while Northern Irishman Darren Clarke, the former Open Championship winner, carded a two-under-par 70 in the $1.3 million OneAsia co-sanctioned tournament.
The 57-year-old Norman bogeyed the first two holes of his opening round before deciding he could not continue while veteran home player Peter Senior, 53, who became the oldest Australian Open champion last weekend, shot a four-under-par 68.