Dayana Yastremska says it is "nice to make history" after beating Linda Noskova to become the first qualifier since 1978 to reach the Australian Open semi-finals.
Ukraine's Yastremska breezed past the Czech teenager 6-3 6-4.
Ranked 93rd in the world, she has won eight matches in a row in Melbourne.
"It's something new for me and for my generation because the last time it happened was a long time ago," Yastremska said.
She will face either Chinese 12th seed Zheng Qinwen or Russia's Anna Kalinskaya for a place in Saturday's showpiece.
Yastremska, 23, is the second qualifier in the Open era to reach the Melbourne Park last four after Christine Dorey in the 1978 tournament.
"I think it's nice to make history because at that time I wasn't born," Yastremska said.
"I was a little bit nervous, but at the same time tired. I think I was a little bit too emotional.
"Today before my match I got angry at the practice of my coach. But that's fine, because I could put my emotions away."
Yastremska is two wins away from emulating Emma Raducanu, who became the only qualifier in history to win a major title with her 2021 US Open triumph.
She was a highly-rated prospect as a teenager, having risen to inside the world's top 25 as a 19-year-old before being given a provisional ban for a failed doping test in January 2021.
Yastremska denied any wrongdoing and the suspension was lifted after six months, with an independent tribunal accepting her positive test was the result of contamination.
She has beaten Grand Slam champions Marketa Vondrousova and Victoria Azarenka on her way to the last four.
Having needed three sets to come through her three qualifying matches, Yastremska has dropped just one set in her five main-draw encounters.
After her win she wrote a message of support for Ukrainian fighters on the camera lens, amid the ongoing invasion of the country by Russia.
"I have a dream since I'm a child and that's what was moving me forward no matter what happens," she said.
"I had a lot of difficult situations and I don't want to talk about it right now. Maybe some other time I can explain it and the story will sound completely differently.
"But for now I can say is that I just, I don't know, I relaxed and I try to enjoy what I'm doing."
BBC