Melbourne's Gabi Ruffels has won her first American collegiate tournament.
And capping a great day for the Aussie women, Queenslander Robyn Choi finished third in the early-season event in Chicago.
Ruffels, 18, in her sophomore season at the University of Southern California, hung tough in the final round of the Windy City Collegiate.
The former Victorian state representative's big day didn't end there, with her effort also spearheading her Trojans to victory in the teams event.
Ruffels was heartily praised by USC boss Justin Silverstein, who also notched his first win as head coach of the women's team.
"Gabi played beautifully all week and her stellar play was able to pace us against this loaded field," Silverstein told USCTrojans.com.
Ruffels, who carded rounds of 69-66-71 on the par-72 Westmoreland layout, finished at 10 under to win by a stroke from Arizona State's Raquel Olmos.
"I knew from the start of the day that I just had to stay steady because conditions weren't easy," Ruffels said.
"I actually didn't know the score coming down the final nine, but just focused on trying to beat Raquel, who was in my group."
The pair finished well clear of the field with University of Colorado star Choi in a share of third at three under par.
Both Ruffels and Olmos mixed three birdies and two bogeys in the final round.
Tied after 11 holes, the Australian went ahead by two with a birdie on 12 as her opponent bogeyed. Olmos pulled to within a stroke with a birdie on 15, but both players parred the final three holes, with Ruffels drilling a 1.5m par putt for victory.
Ruffels fired her low collegiate score in the second round with an incredible nine birdies and a bogey before a closing double-bogey prevented something even more special.