At the 2015 Australian Open, 19-year-old American Madison Keys made her first Grand Slam semifinal. She'd beaten Venus Williams to get there, and would be denied an appearance in the final by eventual champion Serena Williams.

On Thursday, a decade later, 29-year-old Keys smashed her way into her first Aussie Open final, beating world No. 2 Iga Swiatek with a combination of power and relentlessness that Swiatek was unable to defeat. Keys, seeded 19th and playing the best tennis of her life, overcame every challenge Swiatek threw at her, emerging with a thrilling 5-7, 6-1, 7-6(8) victory in two hours and 35 minutes.

Swiatek had been cruising through the tournament before meeting Keys, dropping zero sets and losing a grand total of 14 games through five matches. But Keys challenged Swiatek with her power, smashing seven aces and a stunning 36 winners, never letting Swiatek get into rhythm. Keys took Swiatek to the limit in the first set, giving Swiatek her first real challenge of the entire tournament. Once Swiatek won the set, it felt like she had finally gained control of the match.

Keys then absolutely dominated Swiatek in the second set. It's rare to see Swiatek be nearly non-competitive in any set against any player, but this was one of those times. Keys was relentless, shutting Swiatek down at every opportunity, overwhelming her with the sheer speed of her returns. She built a 5-0 lead over Swiatek in just 18 minutes and won the set in just 26 minutes.

After two stunning sets, the third ending in a winner-take-all tiebreak was perfection. Keys and Swiatek battled for every point, but with an early 5-3 lead it seemed like Swiatek would win with ease. Keys, however, wouldn't go away. She chased Swiatek, never letting her get too far ahead, until she finally tied at 7-7. She smashed her seventh ace of the match to tie Swiatek at 8-8, then won her 10th and final point on a Swiatek unforced error.

After meeting Swiatek at the net, Keys crumbled to the ground and cried, then sobbed into her towel. Saturday's final match is just the second Grand Slam final of her career and her first in eight years.

Keys has never won a major, and she'll have a difficult time getting past No. 1 seed Aryna Sabalenka, who dispatched Paula Badosa 6-4, 6-2 in 86 minutes to make the final. Sabalenka, who is seeking her third consecutive Australian Open trophy, also deals in power, and like Swiatek has had a relatively easy path to the final. She's dropped just one set in the six matches she's played leading into the final, and has beaten the 27, 14, and 11 seeds on her way. But if Keys can use her power smartly and play the kind of tennis she played Thursday, she has a genuine shot at beating the reigning queen of Melbourne Park.

The tennis landscape has changed a lot in the 10 years since Keys lost her maiden Grand Slam semifinal in Melbourne. But in some ways it hasn't changed at all. There is always a powerful foe to defeat, whether it's Serena Williams or Sabalenka. But now, with a decade of tennis under her belt, we've seen that Keys has the ability to marshal all her tools — both physical and mental — to challenge her opponent. In Saturday's final, she controls her own destiny.