Coco Gauff saved two match points on her way to a three-set victory over teenage French Open winner Mirra Andreeva which set up a semi-final showdown with newly-crowned world No 1 Elena Rybakina.

It was a horrible start for 2023 champion Gauff, whose serve and forehand deserted her as she lost the first set in just 26 minutes, hitting only three winners and making 14 unforced errors.

She improved in the second which culminated in a tie-break, during which Russian fifth seed Andreeva squandered two chances to take the match.

That broke Andreeva's spirit and she risked being defaulted after hurling her racket towards her chair, inadvertently sending it spinning towards a camera operator who had to dodge out of the way.

Gauff eventually won 2-6 7-6 (7) 6-2 and revealed she took inspiration from a fellow American's comeback on Tuesday.

"I just had to reset," Gauff said. "I came out at the start, not feeling the ball, giving her too many free points.

"Mirra was playing a great level, but when I went to the restroom after the first set, honestly I was thinking about Frances Tiafoe and how he came back yesterday.

"We all want to do well in front of this crowd. I was trying to leave the court with no regrets, I didn't know what outcome would come. You guys really helped pull me through."

Earlier, Rybakina clinched the world No 1 spot after beating Qinwen Zheng to book her place in the last four.

The 27-year-old from Kazakhstan will usurp Aryna Sabalenka, whose 99-week reign at the top of the rankings will end on Monday.

Rybakina, the Australian Open champion, has been chasing down Sabalenka all year and will be No 1 for the first time in her career even if the Belarusian goes on to win a third consecutive title.

But Rybakina will have something to say about that as well, having reached the last four at Flushing Meadows for the first time.

"It's just a number right now, I'm only in the semis and the goal is to win every tournament I play," she said. "I feel like I just need to focus on my game and enjoy tomorrow."

Rybakina dropped a set for the first time this fortnight but hit back strongly in the second.

And Zheng's near-12 hours on court, through three qualifying matches and five in the main draw, finally caught up with her in the decider as Rybakina won 3-6 6-1 6-4.

"It's tough to find words," added Rybakina. "It was a very difficult match, lot's of nerves, maybe not the highest level but I'm glad I pushed through.

"I didn't start that well, I was too negative. It was a lot of unforced errors but I told myself to keep on fighting."

Zheng was enjoying an Emma Raducanu-style run in New York but, although the 23-year-old from China's fairytale eventually came to an end, she is now back on the verge of the top 50 having slipped to 121 after elbow surgery.

Sky Sports Tennis' Tim Henman:

"It ended up being a really good performance.

"It wasn't the best start from Rybakina, Zheng had something to do with that, but the way she responded in the second and third sets was impressive.

"She was more aggressive from the back of the courts. In that third set, when it was tight, Rybakina really did show her class."

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