Dayana Yastremska, Zheng Qinwen in 1st Slam semis at Aussie Open

Dayana Yastremska and Zheng Qinwen both earned spots in their first Grand Slam singles semifinal, with Yastremska cruising to a straight-sets victory and Zheng shaking off a sluggish start.

Yastremska, the 93rd-ranked Ukrainian who had to qualify for the main draw, wrapped up a 6-3, 6-4 victory over Linda Noskova in 78 minutes. She is only the second qualifier to reach the women's singles semis at the Australian Open in the Open era, after Christine Matison in 1978.

"It's nice to make history because at that time I was not born, I'm 2000," she said. "I'm super-happy, very tired."

Noskova beat top-ranked Iga Swiatek on her way to the quarterfinals and struck first against Yastremska, breaking for a 2-1 lead in the first set.

But Yastremska broke back immediately, and from that moment on, Noskova was always playing catch-up. The Ukrainian broke again to lead 5-2 and served out for the set. One break, in the seventh game of the second, was enough to seal victory.

"I was a little bit nervous, but at the same time tired. I think I was a little bit too emotional," Yastremska said. "Before my match, I got angry at the practice [with] my coach. But that's fine, because I could put my emotions away. Yeah, another step is done."

After dropping the first set, the 12th-seeded Zheng was able to outclass Anna Kalinskaya of Russia for a 6-7 (4), 6-3, 6-1 win.

Kalinskaya, playing in her first Grand Slam quarterfinal, gifted the opening break of the match with a double fault, but Zheng returned the favor immediately and the duo were locked until the tiebreak after more shaky displays on serve.

Zheng, who reached the US Open quarterfinals last year, came under pressure when she hit a forehand wide to hand Kalinskaya two opportunities to take the opening set, and the Russian finished it with a big backhand.

Zheng then trailed 3-2 in the second set before winning 10 of the next 11 games. After Kalinskaya held serve to open the third, Zheng won 12 straight points. She led 4-1 when Kalinskaya needed a medical timeout for treatment on her upper right leg and returned to finish off the match quickly after the break.

"Really excited. First time for me," said Zheng, who will move into the top 10 after the Australian Open. "Really happy to be in the semifinals, especially with such a good performance like this."

Defending champion Aryna Sabalenka and US Open winner Coco Gauff will also play Thursday for a spot in the final.

The Associated Press and Reuters contributed to this report.