Ash Barty reached her first Grand Slam final after ending American 17-year-old Amanda Anisimova's run in a nerve-ridden semi-final at Roland Garros.
Momentum swung in ridiculous proportions on Suzanne-Lenglen as the Australian came through - on her sixth match point - 6-7(4) 6-3 6-3 in blustery conditions.
"I fought my hardest, it's just incredible," said Barty. "I went away from what was working but I am proud of the way I fought and found a way back into that match. It was cold, windy, very tough for the both of us.
"It's incredible, it's an amazing journey that I've been on. I can't wait to see what happens."
Barty collapsed from 5-0 ahead in the first set, losing six games on the spin before throwing away another lead in the tie-break.
But she fought back magnificently from 3-0 behind in the second set, reeling off a seven-game streak as she regained control of the match.
Anisimova, clearly overcome by the occasion, could not settle in the decisive set as her sensational run in Paris - featuring wins over defending champion Simona Halep and Aryna Sabalenka - came to a sad conclusion.
Barty will face Marketa Vondrousova in Saturday's final after the Czech 19-year-old beat Britain's Jo Konta in straight sets.