But Victorian Josh Younger bounced back from an 18th hole disaster to claim a long-awaited maiden tour victory in a playoff.

The breakthrough victory and $72,000 winner's cheque will give world No.963 Younger's career a huge boost.

But it could have been a very different story for a man who already had three runner-up finishes.

The 35-year-old Younger was on track for the title when he arrived at the 18th at Sydney's Twin Creeks course with the lead at 19-under, but he hit his tee shot in the water and took a double bogey.

However, Smyth dropped a shot at the par three 17^th, resulting in a playoff, when they were one shot clear of exciting youngster Min Woo Lee (73), as Justin Warren (-15) also found the water on the final hole.

Younger holed a putt from off the 18th green for par on the first extra hole to continue the playoff as Smyth made a regulation par. And he clinched the title with a six-foot birdie putt after a superb approach shot when they played the hole again, as Smyth missed from 25 feet.

"It's a relief. I've been (on tour) 10 years. I got pipped in a playoff in New Zealand PGA in 2016, finished runner up at the (Australian) Masters...it's just so hard to win, that's the reality of it," said Younger, who shot a nine-under 63 to lead after the first round.

"Normally when you make six down the last it's all over, you need things to go your way. But it's a massive relief."

Port Kembla's Jordan Zunic finished tied for 15^th at nine-under, while Lincoln Tighe was tied for 51^st at -3. AAP

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