Magda Linette will meet fifth seed Aryna Sabalenka in the Australian Open semi-finals after she beat Karolina Pliskova to continue her dream run.
The Polish world number 45 had previously never gone beyond the third round of a Grand Slam in 29 attempts.
But she produced a fearless display in a 6-3 7-5 win over Czech two-time major finalist Pliskova on Rod Laver Arena.
Read More: Rybakina breezes into Australian Open semi-finals
Belarusian Sabalenka defeated Croatia's Donna Vekic 6-3 6-2 to reach her fourth Grand Slam semi-final.
"I'm so emotional. I can't really believe it. It is really a dream come true. I'm super grateful and happy," Linette, 30, said.
"I will never forget this. This will stay with me for life."
Two-time Australian Open winner Victoria Azarenka plays Wimbledon champion Elena Rybakina in the other semi-final on Thursday.
Source: BBC