Poland’s Adrian Meronk shot a closing 66 to beat home favourite Adam Scott to the men’s Australian Open title by five shots while South African Ashleigh Buhai won the women’s event.
England’s Kipp Popert won the All Abilities title for para-golfers.
Meronk became the first Pole to win on the European Tour at July’s Irish Open and added a second title in Melbourne.
The 29-year-old left former Masters champion Scott trailing at Victoria with his superb four-under final round.
South Korea’s Jiyai Shin missed a five-foot birdie putt that would have forced a play-off in the women’s event, which was played alongside the men’s for the first time at the Australian Open.
Meronk, a contender for Europe’s Ryder Cup team next year, enjoyed a much more dominant victory and sealed his triumph with a 40ft eagle putt on the 18th.
He said: “To finish like that on the 18th hole, it’s unreal.
“Adam was always my role model growing up. Beating him in the final group in front of big crowds in Australia is just quite an unbelievable experience.”
The men’s and women’s Australian Open events had equal prize money of £940,000.