Kubler — who had not played at the Australian Open since 2019 — defeated Argentina’s world number 44 Sebastian Baez 6-4, 6-4, 6-4 on John Cain Arena, his victory coming 13 years after he made his debut in the tournament’s main draw as a 16-year-old. The result set up a clash with Russia’s experienced 18th seed Karen Khachanov.