The amiable 22-year-old's life changed in an entirely different manner on Sunday, when he won the $NZ1 million ($A961,000) New Zealand Open in Arrowtown in just his fourth start as a professional.

Zunic missed his PGA Tour of Australasia tour card at qualifying school earlier this year and only qualified for the open courtesy of a top-10 at the NZ PGA Championship last week, for which he was a Monday qualifier.

Now, the Wollongong native will receive a two-year exemption in Australasia and three tournament invites on the more lucrative Japan Golf Tour.

He also received a winner's cheque for $171,000, plus an extra $12,000 for winning the pro-am with his partner Maryanne Marlow, a member at The Hills.

No wonder there were tears as he reflected on an emotional journey during the past 18 months, and setting himself up for a career that could so easily have not eventuated.

In August 2013 he was unsure if he could ever play golf again, having been a passenger in a major accident with fellow amateur players. Zunic was hospitalised for a week with injuries that included a triple-fracture of his left elbow, and bad head cuts and a significant loss of blood, and did not play golf for several months as he was bed-ridden.

"It was tough coming back from that," he said. "I didn't know whether I'd be able to play golf again. Since then, it's been a bit of a rollercoaster ride. I've played good, and then not so good.

"No matter how bad things got, I had that determination to get better, because this is where I want to be. I worked my butt off, and it's nice to get some rewards for your hard work."

Zunic felt getting over that crash helped him with the significant mental side of golf, which he works hard on with his sports psychologist.

"When I started playing again, I just felt so grateful to be breathing and out there playing golf. I could have easily died, and that actually helped me play better.

"The first six months there were some medical issues I had to get over. Once I got over them, I feel like it's really built character for me and made me a little wiser.

"I know it was horrible at the time but I feel like it's made me a stronger person. As my dad always says, everything happens for a reason."

Zunic made a sensational birdie at the 72nd hole to win the Brodie Breeze Trophy.

He walked up the 18th fairway at The Hills tied for the lead with compatriot David Bransdon at 20-under par, but hit the 9-iron of his life as he rattled the flagstick from 150m and then popped in the two-foot birdie putt to seal victory.

"I picked my target, and when I hit it, it felt perfect," he said. "I'm still in disbelief. I'm trying to pinch myself to say that this happened.

"I can't wait to start the journey. This is only the beginning."

After speaking to media, his next port of call was his parents.

"I can guarantee you mum will be crying. That's where I get the tears from. I got mum's soft personality," he laughed. "All those emotions from all those hard times ... I'm sure they'll be in as much disbelief as me."

Zunic finished with a six-under 66 and at 21-under for the week, winning by a shot from the Bransdon who had an eight-under 64 and birdied eight of his final 10 holes, including a spectacular chip-in at the par-three 16th, to almost pull off a remarkable win.

But the 41-year-old journeyman paid the ultimate price for a bogey at the 18th.

Australian Kristopher Mueck, 25, was third at 18-under.

Wellington's Harry Bateman finished as the leading New Zealander, carding a five-under par 67 in the final round to get to 14-under and tie for 10th.

There was some silverware for New Zealand, though, with Josh Munn winning the Bledisloe Cup as the leading amateur. He was the only one to make the cut and finished at 10-under, tied for 23rd.