United States' Tennys Sandgren changes his shirt during his match against Australia's Alex De Minaur during their first round match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Feb. 9, 2021.(AP Photo/Hamish Blair)

Spain's Carlos Alcaraz serves to Botic Van de Zandschulp of the Netherlands during their first round match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Feb. 9, 2021.(AP Photo/Hamish Blair)

Spain's Paula Badosa makes a backhand return to Russia's Liudmila Samsonova during their first round match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Feb. 9, 2021.(AP Photo/Andy Brownbill)

Victoria Azarenka of Belarus reacts during her match against United States' Jessica Pegula in their first round match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Feb. 9, 2021.(AP Photo/Rick Rycroft)

Spain's Carlos Alcaraz celebrates a point win over Botic Van de Zandschulp of the Netherlands during their first round match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Feb. 9, 2021.(AP Photo/Hamish Blair)

Spain's Rafael Nadal reacts after defeating Serbia's Laslo Djere during their first round match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Feb. 9, 2021. (AP Photo/Rick Rycroft)

United States' Coco Gauff makes a forehand return to Switzerland's Jil Teichmann during their first round match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Feb. 9, 2021.(AP Photo/Hamish Blair)