Adelaide International: Aryna Sabalenka self-destructs to derail Australian Open build-up
Aryna Sabalenka self-destructed on her serve as 100th-ranked Kaja Juvan notched the biggest win of her career, 7-6 (8/6), 6-1.
Adelaide: Aryna Sabalenka's Australian Open preparations took a hit when the world number two exited the season-opening Adelaide International in the second round on Wednesday.
The Belarusian, who is yet to win a Grand Slam, self-destructed on her serve as 100th-ranked Kaja Juvan notched the biggest win of her career, 7-6 (8/6), 6-1.
After a close first set, Sabalenka's service action deserted her in the second, virtually handing the match to her Slovenian opponent.
Sabalenka served 18 double-faults in the match — 11 in the second set — with many of her second serves either hitting the base of the net or missing the court completely.
She only won four points on serve in the second set and at one stage raised her arms in triumph when she landed a second serve.
Juvan, who went into the match as the world number 100 but will now finish the tournament ranked at least 83rd, said she felt sorry for Sabalenka in the second set.
"I really enjoyed the first set -- I love it when the match is tight and it's competitive," the 21-year-old said.
"I felt a little sorry for her at some points. I knew she was not doing the best with her serve and we all know how that feels.
"But I was telling myself it can turn at any point so I was trying to stay there until the end."
American Shelby Rogers continued the upsets when she ousted world number six Maria Sakkari of Greece in three sets.
After Rogers took the first set on a tiebreak and led 2-0 in the second, third-seed Sakkari won six straight games and appeared to be taking control.
But Rogers proved slightly more consistent in the third, winning 7-6 (7/5), 2-6, 6-4 to set up a quarter-final against seventh seed Elena Rybakina of Kazakhstan.
World number one Ashleigh Barty will begin her Australian Open warm-up campaign when she faces American prodigy Coco Gauff later Wednesday.
Ons Jabeur and Jessica Pegula, both finalists in Madrid, have moved up to career best in latest WTA Rankings.
Alexander Zverev succumbed in 62 minutes to Carlos Alcaraz but was unhappy that on the previous two nights he had been last on court.
Former German tennis star Boris Becker was handed a two-and-a-half-year jail sentence in a bankruptcy case.