The 18-year-old Czech overcame severe fatigue to defeat Azarenka 6-4 6-7 (3-7) 7-6 (8-6) in a seesawing quarter-final stretching three minutes shy of three hours on Friday.
A first-round winner over third seed Daria Kasatkina, Noskova has now won five consecutive matches in only her sixth appearance in the main draw of a WTA event.
Her reward is a semi-final shot at either world No.2 Ons Jabeur or exciting young Ukrainian Marta Kostyuk, who were contesting the fourth and last quarter-final at Memorial Drive.
Win or lose, Noskova is already guaranteed a massive rankings boost from No.102 to the world's top 70 following her breakout run in the South Australian capital.
World No.5 Aryna Sabalenka was the first woman through to the semi-finals following a straight-sets win over Marketa Vondrousova.
Sabalenka overcame some more serving troubles to defeat the 2019 French Open runner-up 6-3 7-5.
Sabalenka offset three double-faults with four aces and served out the match at the second time of asking.
"It was a touch match. She fought until the end. I am really happy I was able to win this match," second-seeded Sabalenka said.
"I am staying really calm and I feel at home here. That is why I am playing really well. I haven't dropped a set yet and hopefully I will keep going like that."
Sabalenka's notoriously high double-fault count has been the one element of her big game that has prevented the Belarusian from breaking through at grand-slam level.
But the 2021 season-ending runner-up hopes her serving woes are behind her after working with a psychologist as well as seeking some help from Australian Mark Philippoussis.
"I had a really tough year last year and I worked a lot on my serve. Thank God, it is finally working," Sabalenka said.
"I am trying to work on my serve and stay calm no matter what happens."
Sabalenka will play Irina-Camelia Begu for a spot in the title match after the Romanian upset fourth-seeded Russian Verinoka Kudermetova 7-5 6-4 in the second quarter-final.
