Melbourne - Fourth seed Elina Svitolina ended the first Grand Slam odyssey of 15-year-old Marta Kostyuk in straights sets on Friday.
The Ukrainian world number four breezed past her compatriot 6-2, 6-2 in just 59 minutes on a searing day on Rod Laver Arena.
"It's very special for me to get past the third round," said Svitolina, who will be in the last 16 for the first time in Melbourne where she will face another qualifier, Denisa Allertova.
"It's sad I was playing another Ukrainian girl."
Kostyuk had been labelled the "future of tennis" by some observers after becoming the youngest Australian Open second-round winner since "Swiss Miss" Martina Hingis in 1996.
But she produced a nervous, error-strewn display against Svitolina and was inconsolable as she returned to the locker room.
"She's definitely got a bright future," said Svitolina. "We'll be hearing a lot more about her."
Results from the Australian Open on Friday:
Kyle Edmund (GBR) bt Nikoloz Basilashvili (GEO) 7-6 (7/0), 3-6, 4-6, 6-0, 7-5
Petra Martic (CRO) bt Luksika Kumkhum (THA) 6-3, 3-6, 7-5
Denisa Allertova (CZE) bt Magda Linette (POL) 6-1, 6-4
Elise Mertens (BEL) bt Alize Cornet (FRA) 7-5, 6-4