Scott Draper and Samantha Stosur thrilled the Australian Open crowd with victory over Kevin Ullyett and Liezel Huber in the mixed doubles final.
The unseeded Australians came through 6-2 2-6 7-6 against the fourth seeds.
"We've got a Grand Slam title now and no one can take that away from us," said Draper, who was a late replacement for fellow countryman Todd Reid.
Fellow Australian Alicia Molik won the women's doubles on Friday alongside Russia's Svetlana Kuznetsova.
Draper played in his first professional golf event on Friday morning, missing the cut in the Victoria Open after shooting an opening 79.
"Scott's having a bit of a blinder," said Zimbabwean Ullyett, who won the men's doubles with Wayne Black on Saturday.
"He's one of the luckiest guys in the world, to be able to go out in the morning and play golf and then come out in the afternoon and win a Grand Slam title.
"He's the envy of the male population."
Stosur said: "We weren't going to play together, but my partner called me up the night before and told me he wasn't going to play.
"So I called up Scotty and he agreed to play."
Draper added: "I've had a blast this two weeks.
"The phone call from Sam was a beauty, and thanks to the organisers for a wild card.
"That was a good decision."