Aryna Sabalenka and Madison Keys through to US Open semi-finals

The second seed from Belarus cruised into the last four at Flushing Meadows for the third straight year with a commanding 6-1 6-4 victory over Chinese youngster Zheng Qinwen in an hour and 13 minutes.

Zheng, 20, playing in her first grand slam quarter-final, won just four of the first 24 points of the match as Sabalenka raced into a 5-0 lead.

She stopped the bleeding by holding serve in the sixth game, but Sabalenka wrapped up the first set in only 27 minutes.

Zheng, seeded 23, restored some pride in the second but a break in the seventh game ensured Sabalenka became the first woman to reach the semi-finals of all four grand slams in the same year since Serena Williams in 2016.

"I'm super proud of myself and my team that we have been able to adjust to different conditions, different courts. We were able to bring this consistency in my game," she said.

"Yeah, this is something I'm really proud of, and it's just unbelievable and I'm just super happy right now that I'm being able to do this."

Sabalenka has dropped just 21 games in the 10 sets she has played over five rounds in New York.

The 25-year-old will take over from Iga Swiatek at the top of the rankings on Monday, ending the Pole’s 75-week reign

She added: "You know, I'm super happy with this achievement in my career, but, I mean, it's not a big change.

"You know, I mean, I have been number two. Now I'm number one. It's just a difference of position in the draw. I still have to bring my best tennis. I still have to play my best. People will try to chase me and get me.

"But it just an extra motivation for me. You know, seeing them, like, really trying their best to beat me, it's, like, an extra power and energy for me to keep playing, keep pushing, keep getting better."

Sabalenka will face American 17th seed Madison Keys on Thursday night.

Keys, a former Flushing Meadows runner-up, beat Wimbledon champion Marketa Vondrousova 6-1 6-4.

"She's obviously a phenomenal tennis player... there is a reason she's going to be No. 1 on Monday," Keys said of Sabalenka.

"She has a ton of power. She serves really well. To be quite honest, the year that she was able to have with the serving troubles that she had, I think it just shows she's an incredible competitor and fighter. I mean, she's really, really good.

"I think tomorrow it's definitely going to be a lot of who can get in charge of the point as early as possible, because I feel like both of our games, if you get behind in the point it's a lot harder to get back to neutral and then get back on the aggressive side."

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