The world No.1 had been the steadiest force in a wildly unpredictable fortnight until Wednesday, but she lost her grip on her bid for a maiden Roland-Garros title on a blustery day on Court Philippe-Chatrier, dropping the final ten games as she fell to Diana Shnaider, 3-6, 7-5, 6-0.

The No.25 seed's victory means that a first-time Grand Slam champion will be crowned on the women's side in Paris on Saturday.

“Honestly, I'm speechless,” a victorious Shnaider told the crowd. “Obviously today there were tough conditions with the wind, and it was my first time playing Aryna – I was super nervous being in the quarterfinals for the first time."

Twenty-two-year-old Shnaider earns her first career win over a reigning No.1 and moves on to face Polish qualifier Maja Chwalinska in the semifinals.

Top-seeded Sabalenka was dominant from the start of the contest but slowly began to wilt under constant pushback from Shnaider.

A two-game run by the bandanna-touting southpaw put her on the cusp of recovering from a double-break deficit in the opening set, but she hooked a forehand long with Sabalenka serving at 5-3, 30-40, effectively ending her rally, and the 49-minute set. 

Down a double-break in the second set at 4-1, Shnaider again reclaimed one of the breaks – and then the second – as she snatched the middle set despite being two points from defeat with Sabalenka serving at 5-4.

"I feel like in the first set I was just trying to adjust to her game, and then to the conditions, to the winds, and trying to figure out how to play," Shnaider said.

“I was like, ‘It's okay, it's tough conditions, she's world No.1, I will just try to do my best until the end, and we'll see how it goes.'

"I feel like in the third set I finally found my rhythm and how to play. Where to be a little more on defence and where to attack. I feel like the third set was the one that I should have been aiming for from the beginning."

Shnaider broke open the contest with a run of nine consecutive games that took her from a set and 5-3 down to 5-0 up in the third.

"I just think it's a combination of everything," Sabalenka explained. "You overthink, then you make easy mistakes, then you miss opportunities.

"Then the other player on the other side stepping in and start playing a bit more aggressively and more free, kind of fearless."

Then came the tenth consecutive game, and jubilation.

"I don't know when was the last time that happened to me, that I lost 10 games in a row," Sabalenka said. I guess mentally I got into very deep, dark hole over there, and I just couldn't get back mentally on track."