NEW YORK -- During her 37-match win streak, Iga Swiatek tallied a flurry of impressive wins spanning three different surfaces. But it was the third win of her century-best run that would unlock the form and confidence that transformed the 21-year-old into the most dominant force in the women's game.

That win came against Aryna Sabalenka. 

Going into Doha in February, two of Swiatek's three losses this season came at the hands of players with blistering power. In the Australian Open semifinals, it was Danielle Collins. In Dubai it was Jelena Ostapenko.

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Swiatek has not hidden her discomfort at facing "big hitters," as she called them, players who had the pace to diffuse her spectacular court coverage and dismantle her forehand. 

And so it was stunning to watch Swiatek stand toe-to-toe with Sabalenka from the baseline and, quite frankly, outhit one of the biggest hitters in the game and win 6-2, 6-3 in Doha to make her first WTA 1000 hard-court semifinal. The win validated everything Swiatek's new coach, Tomasz Wiktorowski, had been telling her, encouraging her to let loose and embrace a more aggressive style.

"I wanted always to be solid and be the kind of clay-court player who is going to play topspin and stay back, but really, right now tennis is getting faster and faster," Swiatek said in Doha. "Players who are attacking and leading are winning. I wanted to also learn how to do that."

Doha: Swiatek bests Sabalenka to reach 1st hard-court WTA 1000 SF

The rest was history. Swiatek ran through the tour for four months by layering power over her rock-solid base game. If she's struggled during the North American hard courts, it's precisely because that aggressive style has been more difficult to pull off consistently as she's tried to adjust to the lighter balls used during the swing. Having scrapped through the early rounds, Swiatek found her patience in a hard-fought 6-3, 7-6(4) win over No.8 Jessica Pegula. 

"I feel like it just clicked," Swiatek said after the win. "I was able today to use my intuition a little bit more. I didn't force myself to do every step right, all this technical stuff that I've been working on. It was more natural today."

Swiatek will face down the Sabalenka challenge for a fourth time this season in Thursday's US Open semifinals. Swiatek leads the head-to-head 3-1, winning all six sets they have played this year. Including her quarterfinal win against Sabaleka in Doha, Swiatek also bested her in the Stuttgart final and Rome semifinals. Only once during that six-set span did Swiatek lose more than two games in a set. 

In Doha, Swiatek admitted she was zoning. Stuttgart and Rome were played on her favorite surface, clay. Sabalenka was desperate to be the one to snap her streak and struggled to control her frustration. But it will be a different Sabalenka on Thursday, one who is in dangerous, free-swinging form.

The World No.6 came into the tournament without back-to-back wins since June. In the second round, she was inches from being ousted from the tournament. From a set and 5-1 down, Sabalenka saved two match points -- with the help of a net cord -- to defeat Kaia Kanepi 2-6, 7-6(8), 6-4. 

Sabalenka posted two quality wins against Danielle Collins and Karolina Pliskova in her last two rounds. 

Sabalenka says her past two Slam semifinals have prepared her to go into Thursday with no expectations. She conceded that the pressure got to her the last two times, in three-set losses to Pliskova in the 2021 Wimbledon semifinals, and Leylah Fernandez here last year.

"I know it's going to be tough," she said, "and I know I have to work for it, and I have to fight for it."