Underdog Madison Keys denied top seed Aryna Sabalenka's place in history after winning a nerve-jangling women's final at the Australian Open on Saturday, while Henry Patten and Harri Heliovaara claimed the men's doubles title.

19th seed Keys started strongly before withstanding a fierce fightback from Sabalenka to prevail 6-3, 2-6, 7-5 and lift her first Grand Slam trophy.

Madison Keys poses with the trophy during the awarding ceremony after the women's singles final between Aryna Sabalenka of Belarus and Madison Keys of the United States at Australian Open tennis tournament in Melbourne, Australia, Jan. 25, 2025. (Xinhua/Ma Ping)

The American slammed 29 winners in a gripping final lasting two hours and two minutes as she prevented Sabalenka from becoming the sixth woman to win three straight titles at Melbourne Park.

Swiss tennis legend Martina Hingis had been the last player to achieve the feat in 1999.

The 29-year-old Keys became the oldest first-time Grand Slam women's winner in almost a decade.

Keys was rewarded for an aggressive approach in a reversal from her timid straight-sets defeat to Sloane Stephens in the final of the 2017 US Open.

Coached by her husband Bjorn Fratangelo, Keys once again showcased her resiliency having claimed her fifth three-set match of the tournament.

It completed a renaissance for Keys, who was a prodigy in her youth and had a professional career breakout when she reached the semifinals at Melbourne Park as a teenager in 2015.

She endured a period in the wilderness, struggling to cope with the expectations, but the triumph in Melbourne lifts her seven spots to an equal career-high No.7 on the WTA rankings.

"To get back to this position and to be able to play the way I played and finish on this strong note, I'm just really proud of myself," Keys told reporters.

"I didn't always believe I could get back to this point, but to be able to do it and win means the world to me," she said. "I had to go through tough things and it made me look at myself in the mirror."

It was a bitter disappointment for three-time Grand Slam champion Sabalenka, whose 20-match win streak in Melbourne came to a screeching halt having lost just one set before the final.

"She played super aggressive. Everything was going her way and I couldn't play aggressive tennis," Sabalenka said.

"When you get to the final, it's trophy or nothing. Nobody remembers the finalist. I go for titles, but I have to be proud of myself. I hope next year I can come back as a better player."

The 26-year-old Sabalenka was heavily favored in the final, but fireworks were expected between two of the biggest hitters in women's tennis.

Keys showed no signs of nerves and her strategy of shortening the points rattled Sabalenka as she stepped into her shots with devastating effect.

Keys broke three times in a dominant opening set, but Sabalenka found her rhythm and rattled off five straight games in the second set before drawing level.

Sabalenka continued to press early in a tense third set, but Keys fended off the barrage as holds of serve were traded across the opening 11 games.

Keys went for broke in the 12th game, attacking Sabalenka's serve to move agonizingly close at 15-40.

After spraying her first match point, Keys sealed victory in style with a sizzling crosscourt winner before her emotions poured out and she was soon in the arms of her husband.

Meanwhile, Wimbledon champions Patten and Heliovaara came from behind to edge third seeds Simone Bolelli and Andrea Vavassori 6-7 (16), 7-6 (5), 6-3 in the men's doubles final.

The blockbuster men's singles final between defending champion Jannik Sinner and second seed Alexander Zverev will complete the 15-day competition on Sunday.

It will be preceded by the women's doubles final between top seeds Katerina Siniakova and Taylor Townsend and No.3 Hsieh Su-wei and Jelena Ostapenko.