Unseeded Latvian Jelena Ostapenko hit back from losing the first set to former world number one Caroline Wozniacki to complete a shock 4-6 6-2 6-2 win in their rain-hit quarter-final on Suzanne-Lenglen.
Teenager Ostapenko had trailed 2-1 in the final set when the pair resumed after a second rain delay, but ripped through the Dane's defences by reeling off five straight games to reach her first Grand Slam semi-final.
She belted 38 winners and made 50 unforced errors as she threw caution to the wind with a high-risk approach that Denmark's conservative Wozniacki had no answer to.
"I love you all," the bubbly Ostapenko told the fans after claiming the biggest win of her career.
Wozniacki, playing in her second quarter-final at the French, had no solution once her opponent found her range.
"She kept me on the back foot...she goes for her shots. Her shots are hard to read, so you don't really feel comfortable at any point in the match," said the Dane.
The world number 47 from Riga finalised the insurance of a double break with several sizzing winners as 11th seed Wozniacki's hopes were crushed in the late evening wind of Roland Garros as the 19-year-old served out the match to love.
Ostapenko, who turns 20 on Thursday when she faces fellow birthday girl Timea Bacsinszky of Switzerland, who will be 28, is the first Latvian woman to reach a grand slam semi and first teenager since since Serb Ana Ivanovic in 2007.
Bacsinszky turns 28 on Thursday, while Ostapenko will leave her teens behind.
"It will be great to celebrate playing tennis here," said Ostapenko. "Lucky her, she's way younger than I am," Bacsinszky joked. "But maybe lucky me, experience-wise."
Bacsinszky completed a 6-4 6-4 win over French hope Kristina Mladenovic in the day's other quarter-final.
Ostapenko's day had not started in promising fashion.
Wicked winds bent the flag poles and red brick dust was whipped up into the players' eyes in the opening games in which Ostapenko could hardly locate the court.
Wozniacki merely had to keep the ball in play to build a 5-0 lead as her unseeded opponent sprayed errors.
Ostapenko's mood was as dark as the menacing black clouds circling above and she gesticulated forlornly towards her mother Jelena, who is also her coach, as shot after shot flew long.
She finally got on the scoreboard in the sixth game, though, as her aggressive game clicked and she began to boss the rallies with a whippy forehand that Wozniacki could not read.
Having clawed her way back to 4-5, the errors returned and Wozniacki took the opening set.
Undeterred, Ostapenko maintained the momentum and had Wozniacki scurrying around behind the baseline as the Latvian walloped the ball into the corners, often finishing rallies by thrashing away mid-court volleys.
Ostapenko carved out a 5-2 lead and Wozniacki looked relieved to get off court when torrential rain arrived to force a three-hour delay.
The stoppage should have helped the Dane but when play resumed Ostapenko continued where she left off, holding serve to level the match.
Wozniacki saved a break point to edge 2-1 ahead in the decider before another rain interruption.
It did little to dampen Ostapenko's fire, though, and it was one-way traffic in the match's third instalment as she raced to a fourth consecutive victory against Wozniacki.
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Nadal sat out an hour-long rain delay and beat Richard Gasquet 6-3, 6-4 on Wednesday night, finishing off the match with two of his eight aces.
Roger Federer has pulled out of the Cincinnati Open with a back injury, meaning Rafael Nadal will be the new world number one in next week's rankings.
Maria Sharapova will play her first Grand Slam event since her doping ban after it was confirmed she was handed a wild card for this month's US Open.
German fourth seed Alexander Zverev upset Roger Federer 6-3 6-4 in the Rogers Cup final in Montreal on Sunday to join the Swiss right-hander as the most trophy-laden player on the ATP Tour this year with five titles.
Ukrainian Elina Svitolina capped a remarkable week in Toronto by beating Dane Caroline Wozniacki 6-4 6-0 at the Rogers Cup on Sunday to capture her tour-leading fifth title of the season.
Wimbledon champion Roger Federer stayed on course for his third Rogers Cup title after defeating Dutchman Robin Haase 6-3 7-6 (7/5) to reach Sunday's final in Montreal.
Danish sixth Caroline Wozniacki, riding high after ousting world number one Karolina Pliskova, beat American Sloane Stephens 6-2 6-3 in the Rogers Cup semi-finals.
Roger Federer reached the Rogers Cup semi-finals on Friday after coming to the net early and often in a straight sets victory over Roberto Bautista Agut on a windy day in Montreal.
Caroline Wozniacki defeated world number one Karolina Pliskova 7-5 6-7(3) 6-4 in a marathon Rogers Cup quarter-finals match in Toronto marred by four rain delays on Friday