United States' Jennifer Brady reacts after winning a point against compatriot Jessica Pegula during their quarterfinal match at the Australian Open tennis championship in Melbourne, Australia, Wednesday, Feb. 17, 2021.(AP Photo/Hamish Blair)

Spain's Rafael Nadal, right, and Greece's Stefanos Tsitsipas pose for a photo ahead of their quarterfinal match at the Australian Open tennis championship in Melbourne, Australia, Wednesday, Feb. 17, 2021.(AP Photo/Hamish Blair)

Greece's Stefanos Tsitsipas hits a backhand return to Spain's Rafael Nadal during their quarterfinal match at the Australian Open tennis championship in Melbourne, Australia, Wednesday, Feb. 17, 2021.(AP Photo/Hamish Blair)

Spain's Rafael Nadal hits a forehand return to Greece's Stefanos Tsitsipas during their quarterfinal match at the Australian Open tennis championship in Melbourne, Australia, Wednesday, Feb. 17, 2021.(AP Photo/Hamish Blair)

Fans cheer for Australia's Nick Kyrgios, back to camera, during his third round match against Austria's Dominic Thiem at the Australian Open tennis championship in Melbourne, Australia, Friday, Feb. 12, 2021.(AP Photo/Hamish Blair)

Russia's Daniil Medvedev hits a backhand return to compatriot Andrey Rublev during their quarterfinal match at the Australian Open tennis championship in Melbourne, Australia, Wednesday, Feb. 17, 2021.(AP Photo/Hamish Blair)

Russia's Andrey Rublev reacts after losing a point to compatriot Daniil Medvedev during their quarterfinal match at the Australian Open tennis championship in Melbourne, Australia, Wednesday, Feb. 17, 2021.(AP Photo/Andy Brownbill)

United States' Sofia Kenin leaves the court following her second round loss to Estonia's Kaia Kanepi during at the Australian Open tennis championship in Melbourne, Australia, Thursday, Feb. 11, 2021.(AP Photo/Rick Rycroft)

United States' Jessica Pegula hits a backhand return to compatriot Jennifer Brady during their quarterfinal match at the Australian Open tennis championship in Melbourne, Australia, Wednesday, Feb. 17, 2021.(AP Photo/Hamish Blair)

Karolina Muchova of the Czech Republic hits a backhand return to Australia's Ash Barty during their quarterfinal match at the Australian Open tennis championship in Melbourne, Australia, Wednesday, Feb. 17, 2021.(AP Photo/Andy Brownbill)

Australia's Ash Barty wipes the sweat from her face during her quarterfinal match against Karolina Muchova of the Czech Republic at the Australian Open tennis championship in Melbourne, Australia, Wednesday, Feb. 17, 2021.(AP Photo/Andy Brownbill)