Naomi Osaka, Serena Williams reach quarters, Dominic Thiem slumps out of Australian Open

Fans remained absent from Melbourne Park for a second day because of the state of Victoria`s coronavirus lockdown and Osaka`s victory was greeted with taped applause piped into the stadium. "I`m tired right now, that was tough," said Osaka, who mixed 40 winners with 36 unforced errors over the contest.