The world number one led by a set and a double-break before exiting the tournament in a blaze of unforced errors, collapsing to a 3-6, 7-5, 6-0 loss in blustery conditions on Court Philippe Chatrier.

Shnaider will face Polish qualifier Maja Chwalinska in the semi-finals on Thursday, with Marta Kostyuk or Mirra Andreeva awaiting the winner in Sunday's final.

"Well honestly I'm speechless, I'm super happy. Obviously tough conditions with the wind," said the 22-year-old Shnaider after beating a top-10 player for only the second time in her career.

"First time playing Aryna so definitely a lot of nerves and I feel the first set was trying to adjust to her game."

Sabalenka was the only Grand Slam champion left in either the men's or women's singles draws at Roland Garros, but belied that status by making a whopping 57 unforced errors.

Shnaider was playing in her first major quarter-final, but now finds herself a strong favourite to reach the final heading into her last-four tie against world number 114 and fellow left-hander Chwalinska.

"Definitely super happy I managed to finish on a good note rather than start on a good note. Definitely a special tournament for me here," added the Russian.

"It's going be a lefty battle so I'm looking forward (to the semi-final)."

Sabalenka's scarcely believable defeat was reminiscent of the way she threw away a strong position in last year's final against Coco Gauff.

The Belarusian was playing in a 14th consecutive Grand Slam quarter-final but failed to become the first woman to make seven straight major semis since Serena Williams.

- Increasingly frustrated Sabalenka -

The top seed raced into a 5-1 lead and eventually sealed the opener on her third set point after initially failing to serve it out.

The second set followed a similar pattern at first, as Sabalenka moved 4-1 in front with a double-break before throwing away her next service game.

Sabalenka became increasingly frustrated as she gifted Shnaider three break points to level at 4-4.

After some animated remonstrating with her box, she recomposed herself enough to hold.

But the 28-year-old's game continued to come apart, as a string of dreadful unforced errors allowed Shnaider to break again and tie up the set at 5-5, with Sabalenka left to gesticulate wildly towards her coaching staff.

Shnaider could not believe her luck as Sabalenka dumped successive forehands into the bottom of the net to finish off the set and send the match into a decider.

The Russian grew in confidence and moved 2-0 up in the third as Sabalenka sprayed eight unforced errors around Chatrier in the space of two games.

Shnaider cruised to victory from there, fittingly securing a semi-final berth when Sabalenka knocked a routine backhand into the net on the third match point.

A stunned world number one was left to trudge off court after winning just 14 points in the deciding set.

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