Defending champion Naomi Osaka is out of the Australian Open after losing in three sets to Amanda Anisimova on Friday.
The two-time champion was one set up against the 20-year-old American, only for Anisimova to battle back and clinch a superb 6-4, 3-6, 6-7 victory in Round 3.
“I'm speechless. I can't stop smiling. I'm just laughing. I absolutely love this,” said Anisimova.
“Going into this match I knew I had to be playing sharp if I wanted to give myself a chance. She [Osaka] is an absolute champion so I knew I would have to step up my game and be aggressive.
“I'm honestly so grateful that I was able to play so well today and get this win. It means a lot.
“Every single day here is an amazing opportunity. I'm just thinking about having fun and I'm looking forward to my next round.”
Osaka missed out on what would have been a mouth-watering clash with world No 1 Ashleigh Barty after the Australian powered into the next round following a routine 6-2, 6-3 win over Italy's Camila Giorgi in just over an hour.
After an early break, the 25-year-old Wimbledon champion fended off three break points to go 5-2 up and then broke Giorgi to seal the opening set.
A break for 4-2 put Barty in charge of the second set and three games later she was bathing in an ovation from the centre court crowd having secured her place in the last 16 at Melbourne Park for the fourth straight year.
“I thought tonight was really clean, I looked after my service games really well,” said Barty. “I was able to keep the momentum going, make returns when it mattered most at the important moments, pretty good performance I think.”
French Open champion Barbora Krejcikova said she hopes opponents are “scared” to play her after pulling off a gritty comeback win against Jelena Ostapenko.
The Czech fourth seed was one of the standout players of 2021 but found herself in trouble at 2-6, 1-3 down to the 2017 Roland Garros winner, before fighting back to clinch the match on Rod Laver Arena 2-6, 6-4, 6-4.
“I hope they are scared of me,” said the 26-year-old Krejcikova. “But, I mean, I don't really know. I think in the locker room we have a really respectful atmosphere, each of us. I hope [when] they see me that they don't want to play me.”
It set up an attractive fourth-round clash with two-time Australian Open champion Victoria Azarenka, who swept past 15th seed Elina Svitolina 6-2, 6-2.
“I think the rise of Barbora has been pretty incredible over the last year and a half,” the Belarusian, who is seeded 24th, said of her next opponent.
“She seems to kind of elevate her game more and more. She has all the good tools to play — she can play aggressive, she can mix it up. Very dangerous player.”
Greek fifth seed Maria Sakkari eased past Veronika Kudermetova of Russia 6-4, 6-1 to move into a fourth-round match against 21st seed Jessica Pegula of the US, who defeated Spain's Nuria Parrizas Diaz 7-6, 6-2.
Another Spaniard, in No 8 seed Paula Badosa, battled to a 6-2, 5-7, 6-4 win over Ukrainian Marta Kostyuk and will now take on American Madison Keys, who held off China's Wang Qiang 4-6, 6-3, 7-6.
“Marta's an insane player and I think she was playing top five level today,” Badosa after beating her 19-year-old friend in a match that lasted two hours and 19 minutes. “She'll soon for sure be one of the best players in the world.”