World number one Iga Swiatek is out of the Australian Open after being stunned by Czech 19-year-old Linda Noskova in the third round.
The Pole, 22, had looked in control but the highly-rated Noskova fought back to win 3-6 6-3 6-4 on Rod Laver Arena.
In the decider the world number 50’s power rocked Swiatek, who was hampered by forehand errors.
“I’m speechless,” said Noskova, who has reached the fourth round of a major for the first time.
“Obviously I knew it was going to be an amazing match with the world number one but I didn’t really think it would end up like this.
“I’m just really glad to get through this round.”
Noskova is playing in the main draw in Melbourne for the first time, having lost in qualifying as an 18-year-old last year, and was making her first appearance on the tournament’s main show court against Swiatek.
She fell to the floor in disbelief after converting her first match point following a tight third set.
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Noskova broke serve for 2-1 in the decider only for Swiatek to up her intensity and level, but that proved to be a false dawn for the world number one, who was broken again at 4-3.
The four-time Grand Slam champion applied pressure at 30-30 when Noskova served for the match but the Czech fired down an ace before a big first serve helped her wrap up the win.
The loss also ended Swiatek’s 18-match unbeaten run, which stretched back to September.
Swiatek’s exit follows second-round defeats for third seed Elena Rybakina, fifth seed Jessica Pegula and sixth seed Ons Jabeur, with only three of the top 10 seeds – defending champion Aryna Sabalenka, US Open winner Coco Gauff and Barbora Krejcikova – left in the draw.
Noskova will play Ukrainian 19th seed Elina Svitolina or Switzerland’s Viktorija Golubic next.
Zheng’s win took two hours and 40 minutes on Rod Laver Arena
Earlier, China’s Zheng Qinwen, the 12th seed, edged out compatriot Wang Yafan in a third-set tie-break to win 6-4 2-6 7-6 (10-8).
Zheng’s win comes 10 years after Li Na became the first Chinese winner of the women’s singles title in Melbourne.
“That final I have watched more than 10 times,” said Zheng, who was 11 when Li won and met her in person for the first time after the win over Wang. “I have a lot of memories.
“I was sitting there in front of TV. I watched from beginning to the end.
Li, who became Asian’s first Grand Slam singles champion by winning the French Open in 2011, beat Dominika Cibulkova on Rod Laver Arena in 2014 to win her second Grand Slam title but retired later that year because of injury.
Zheng will play French world number 95 Oceane Dodin in the fourth round after she beat compatriot Clara Burel 6-2 6-4.
Two-time Australian Open champion Victoria Azarenka progressed with a 6-1 7-5 victory over Latvia’s 11th seed Jelena Ostapenko.
The Belarusian 18th seed trailed 5-2 in the second set and had to save four break points as she served for the match.
Russian Anna Kalinskaya beat American Sloane Stephens 6-7 (8-10) 6-1 6-4 and with Italian Jasmine Paolini awaiting for Kalinskaya in the next round, there is guaranteed to be a first-time major semi-finalist in Zheng’s section of the draw.
Paolini reached her first Grand Slam fourth round by beating Anna Blinkova, who stunned Elena Rybakina on Thursday, 7-6 (7-1) 6-4.
She will face Ukrainian qualifier Dayana Yastremska, who defeated American 27th seed Emma Navarro 6-2 2-6 6-1.
