Austria's Dominic Thiem serves to Bulgaria's Grigor Dimitrov during their fourth-round match at the Australian Open tennis championship in Melbourne, Australia, Feb. 14, 2021.

Spain's Rafael Nadal tries to make a butterfly fly from his hand during his first-round match against Serbia's Laslo Djere, Melbourne, Australia, Feb. 9, 2021

Serena Williams of the United States looks on during her women’s singles semifinal match against Naomi Osaka of Japan, Melbourne, Australia, Feb. 18, 2021.

Spain's Rafael Nadal replaces his headband during his quarterfinal against Greece's Stefanos Tsitsipas, Melbourne, Australia, Feb. 17, 2021.

Russia's Daniil Medvedev reaches to hit a forehand to Serbia's Novak Djokovic during the men's singles final, Melbourne, Australia, Feb. 21, 2021.

Belgium's Elise Mertens (L) and Aryna Sabalenka of Belarus celebrate with their trophy after defeating Barbora Krejcikova and Katerina Siniakova of the Czech Republic in the women's doubles final, Melbourne, Australia, Feb. 19, 2021.

Karolina Muchova of the Czech Republic serves in her women’s singles semifinals match against Jennifer Brady of the United States on day 11 of the Australian Open, Melbourne, Australia, Feb. 18, 2021.

Japan's Naomi Osaka holds the Daphne Akhurst Memorial Cup aloft after defeating the United States' Jennifer Brady in the women's singles final, Melbourne, Australia, Feb. 20, 2021.

The United States' Michael Mmoh makes a forehand return to Spain's Rafael Nadal during his second-round match, Melbourne, Australia, Feb. 11, 2021.

Serbia's Novak Djokovic falls as he celebrates after defeating Russia's Daniil Medvedev during the men's singles final, Melbourne, Australia, Feb. 21, 2021.

Serbia's Novak Djokovic kisses the Norman Brookes Challenge Cup after defeating Russia's Daniil Medvedev in the men's singles final, Melbourne, Australia, Feb. 21, 2021.

Germany's Alexander Zverev in action during his fourth-round match against Serbia's Dusan Lajovic, Melbourne, Australia, Feb. 14, 2021.

Canada's Denis Shapovalov in action during his first-round match against Italy's Jannik Sinner, Melbourne, Australia, Feb 8, 2021.

The United States' Coco Gauff makes a backhand return to Ukraine's Elina Svitolina during their second-round match, Melbourne, Australia, Feb. 11, 2021.

Russia’s Daniil Medvedev smashes his racket during his finals match against Serbia's Novak Djokovic, Melbourne, Australia, Feb. 21, 2021.

Sweden's Mikael Ymer hits a backhand to Greece's Stefanos Tsitsipas during their third-round match, Melbourne, Australia, Feb. 13, 2021.

Play resumes after fans leave during the third round match between Serbia's Novak Djokovic and Taylor Fritz, Melbourne, Australia, Feb. 12, 2021.

Russia's Daniil Medvedev hits a backhand return to compatriot Andrey Rublev during their quarterfinal match, Melbourne, Australia, Feb. 17, 2021.