Melbourne - Ashleigh Barty will play 14th-seeded American Sofia Kenin in the Australian Open semi-finals after the world No 1 defeated Petra Kvitova in straight sets on Tuesday.
The top seed and last remaining Australian in the tournament survived a tough opening set to beat the Czech seventh seed 7-6 (8/6), 6-2 and reach the semi-finals for the first time.
This was revenge for the 23-year-old Barty after two-time Wimbledon champion Kvitova beat her at the same stage last year in Melbourne.
But the down-to-earth Australian is a better player than 12 months ago, winning the French Open last year and hitting the top of the rankings for the first time.
"It's been absolutely incredible. I knew that I had to bring my best today against Petra, and that first set was crucial," said Barty.
Barty is attempting to become the first Australian woman since Chris O'Neil in 1978 win the women's title Down Under.
Kvitova, 29, who suffered severe injury to her left playing hand in a knife attack at her home in 2016, and Barty went toe-to-toe in a crucial seventh game of the first set.
In a game stretching to nearly 10 minutes, Barty fought off five break points to hold serve at Rod Laver Arena, to roars of approval.
In a tense encounter they went to the tie-break, but it was Kvitova who blinked, shanking a forehand long to give Barty the set in 69 high-quality minutes.
Barty, who once gave up tennis to play professional cricket, clenched her fist. Kvitova tossed her racquet into air.
Barty pulled away in the second set as Kvitova wilted in the Melbourne sun.
The Australian sealed the deal with her trademark minimum fuss, booking her spot in the last four with an ace.
Earlier Kenin, Coco Gauff's conqueror, reached her first Major semi-final as the American ended the historic run of Tunisian Ons Jabeur.
The Moscow-born 21-year-old, who defeated 15-year-old Gauff in the previous round, saw off the unseeded Jabeur 6-4, 6-4 and said that she was "super-excited".
"It was a tough match," said Kenin, who moved to New York as a baby with her family with just a few hundred dollars to their name.
Kenin said that holding her serve at 3-2 down in the second set, in a game that stretched to 10 minutes, was a turning point.
"It was a tough moment, she was playing well. I didn't know it was 10 minutes but it felt pretty long," she said.
"But after that I got my momentum and started playing better."
The 78th-ranked Jabeur was the first Arab woman to reach a Grand Slam quarter-final.