Serbia's Novak Djokovic celebrates winning the first round men's singles match against Britain's Jack Draper on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Kirsty Wigglesworth)

Spectators shelter under umbrellas during a rain delay on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Alberto Pezzali)

Spectators shelter under umbrellas during a rain delay on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Alberto Pezzali)

People walk around the grounds on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Alberto Pezzali)

Frances Tiafoe of the US celebrates after winning the men's singles match against Stefanos Tsitsipas of Greece on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Alastair Grant)

Argentina's Federico Delbonis serves to Russia's Andrey Rublev during the men's singles match on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Alberto Pezzali)

Frances Tiafoe of the US celebrates after breaking the serve of Stefanos Tsitsipas of Greece during the men's singles match on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Alastair Grant)

Serbia's Novak Djokovic serves to Britain's Jack Draper during their first round men's singles match on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Kirsty Wigglesworth)

Britain's Jack Draper celebrates winning the first set against Serbia's Novak Djokovic during their first round men's singles match on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Kirsty Wigglesworth)

A steward stands on Centre Court covered with the roof ahead of the men's singles match between Serbia's Novak Djokovic and Britain's Jack Draper on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Kirsty Wigglesworth)

Belarus's Aryna Sabalenka returns a ball to Romania's Monica Niculescu during their first round women's singles match on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Alastair Grant)

Stefanos Tsitsipas of Greece returns the ball to Frances Tiafoe of the US during the men's singles match on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Alastair Grant)

Sloane Stephens of the US celebrates winning a point against Czech Republic's Petra Kvitova during the women's singles match on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Kirsty Wigglesworth)

Poland's Iga Swiatek returns the ball to Taiwan's Su-Wei Hsieh during the women's singles match on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Alastair Grant)

Sloane Stephens of the US celebrates winning the women's singles match against Czech Republic's Petra Kvitova on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Kirsty Wigglesworth)

Frances Tiafoe of the US celebrates after winning the men's singles match against Stefanos Tsitsipas of Greece on day one of the Wimbledon Tennis Championships in London, Monday June 28, 2021. (AP Photo/Alastair Grant)