ADELAIDE, Australia - Ukrainian teen Dayana Yastremska booked the biggest final of her career on Friday, defeating No.6 seed Aryna Sabalenka, 6-4, 7-6(4), at the Adelaide International.

"It's nice. I'm very happy," she said, smiling through her post-match press conference. "And especially in the beginning of the year. I think it brings me some confidence before the Grand Slam, so it's nice to be in the finals."

Yastremska has already won three WTA titles - including two last season on two different surfaces - but all on the International level. Playing her first Premier semifinal, she edged through a tricky second set to overcome the Belarusian in one hour and 44 minutes on Centre Court.

Yastremska and Sabalenka last played at the Internationaux de Strasbourg, which the Ukrainian youngster won en route to taking her first career clay court title.

"I feel comfortable playing with her. She's aggressive. Her style is pretty similar to mine, so I feel very comfortable playing with her, and I like the way she hit the balls. It feels, like, very energetic, but for me, it's pretty comfortable."

Starting the season with new coach Sascha Bajin - noted for his work with the likes of Serena Williams, Caroline Wozniacki, and Naomi Osaka - Yastremska confidently traded booming baseline blows with Sabalenka, who scored her first win over former World No.1 Simona Halep on Thursday.

"I had a good preseason. I work on a lot of things, and I think that's, like, a payoff. I don't know why exactly it's this tournament. I guess Brisbane it was just, like, the tournament I had to feel everything myself.

"Here I started really to feel, with each game, that I'm playing better and better. I think that's why it's like this, like trying to play each match as good as I can. Here I am in the finals."

Putting down strong serves, the teenager made it through the opening set without facing a break point, striking an even nine winners and nine unforced errors. She nabbed the crucial break in the fifth game and sealing the set with an ace.

Yastremska continued that momentum early in the second with an immediate break and hold to consolidate - despite a clever lob from the typically offense-minded Sabalenka.

Maintaining her lead with a searing cross-court backhand, the unseeded Ukrainian had Sabalenka under pressure, missing a forehand putaway at the net and falling behind a break point thanks to another Yastremska winner.

The No.6 seed saved it and stayed within one game thanks to a pair of solid serves, and earned her first break point of the match in the next game, leveling the set on her second opportunity.

"In the second set when I was 3-1 up, I felt a little bit my legs were heavy, and I felt like I got a little bit tired. So I lost my focus, and then, after Sascha came on court, I got some energy, and I really tried to do what he told me. I think I just fought. That's it."

Yastremska twice battled back from being two points from a third set, ultimately forcing a tie-break at six games apiece.

She soon earned a slew of match points - four in total - and secured victory on her third.

In all, she struck 25 winners to just 14 from Sabalenka, who also hit 24 unforced errors to Yastremska's 30. Proving particularly potent on serve, Yastremska won 79% of her first serve points and hit five aces.

Up next for the Ukrainian is either World No.1 Ashleigh Barty or 2019 Australian Open semifinalist Danielle Collins, who upset No.4 seed Belinda Bencic in the quarterfinals.

"I played already with both of them. Ashleigh is definitely a very great player. Collins is more aggressive. But I don't have any preference. I will like to play with both of them."

2020 Adelaide Highlights: Yastremska stops Sabalenka for first Premier final