American Madison Keys wins Australian Open championship - ESPN

MELBOURNE, Australia — Madison Keys said breaking through at the Australian Open for her first Grand Slam title «means the world» after she defeated world No. 1 Aryna Sabalenka in three thrilling sets Saturday.

Keys, the 19th seed, was a big underdog coming into the clash with two-time reigning champion Sabalenka, but she produced her best tennis to win in two hours and two minutes 6-3, 1-6, 7-5.

At 29, Keys becomes the second-oldest first-time women's winner of the tournament after China's Li Na broke through for her win in 2014 at 31.

The American started fast against Sabalenka, who struggled with her serve early. Two double faults helped gift Keys the opening game, and Keys held for 2-0 advantage.

While Sabalenka struggled on her serve, Keys flourished. Through two service games, she had landed all but one of her first serves to put pressure on Sabalenka, who was unable to win her way back to level and was instead broken again for a 4-1 Keys lead.

And while Keys had the chance to serve out the first set not long after, Sabalenka started to lift. She broke Keys, but the seeds of doubt didn't take root for the American, who broke back immediately. Another Sabalenka double fault — her fourth of the set — brought up break point and paved the way for Keys to take the first set 6-3 in just 35 minutes.

Sabalenka's four first-set double faults was her most in a single match in Melbourne, let alone in a set, while her lopsided return of just four winners and 13 unforced errors painted the picture of an uncharacteristically bad start for the Belarusian.

But Sabalenka's record coming back from a set down in Slams had been remarkable. Coming into the final, she was a staggering 10-1 in majors after losing the first set, well