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 struggled and was hampered by forehand errors.
Noskova will play 19th seed Elina Svitolina or Viktorija Golubic in her first fourth-round match at a major.
Swiatek was playing in the main draw in Melbourne for the first time, having lost in qualifying as an 18-year-old last year, as well as making her first appearance on the tournament's main show court.
Noskova fell to the floor in disbelief after converting her first match point following a tight third set.
She broke serve for 2-1 in the decider only for Swiatek to up her intensity, 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.
