American teenager Amanda Anisimova said she was "excited" and did not suffer from nerves after stunning defending champion Simona Halep on Thursday to reach the French Open semi-final against Australian eighth seed Ashleigh Barty.
The 17-year-old downed Halep 6-2, 6-4 on Court Philippe Chatrier to announce herself on the big stage, while Barty saw off 14th seed Madison Keys 6-3, 7-5 to also become a first-time Grand Slam semi-finalist.
She is the youngest American woman to make the last four at a major since Venus Williams at the 1997 US Open, and the youngest to reach the semis at Roland Garros since Jennifer Capriati in 1990.
Still only five women have lifted back-to-back French Open titles in the Open era.
"I feel sad, because every time when I lose, I'm sad," said Halep. "And I'm a little bit upset because I couldn't make my game. I couldn't move normally."
The winner of Anisimova's clash against Barty will face either Britain's Johanna Konta or Czech 19-year-old Marketa Vondrousova in the final.
Anisimova crushed 25 winners past a bewildered Halep, who made 17 unforced errors and served two double faults.
She saved a break point and then dismantled the Halep serve once more to seal the opening set in under half an hour.
Halep, who had thrashed 18-year-old Pole Iga Swiatek 6-1, 6-0 in the fourth round, faced being on the wrong end of a similarly one-sided match when she fell 3-0 down in the second.
Barty also won in relative comfort on Court Suzanne Lenglen to go one better than her run to the Australian Open last eight earlier this year.
The 23-year-old was too consistent for American Keys, hitting 16 winners and four aces.
World number eight Barty is the highest-ranked woman in the semi-finals, ahead of 26th seed Konta and the unseeded youngsters Anisimova and Vondrousova.
But she insisted it would not give her an advantage, saying: "As I just said, all four of us have been playing great tennis. It's a new situation for me. It's a little bit of a new territory."
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