Serbia's Novak Djokovic plays a return to Italy's Matteo Berrettini during the men's singles final on day thirteen of the Wimbledon Tennis Championships in London, Sunday, July 11, 2021. (Steve Paston/Pool Via AP)

Serbia's Novak Djokovic kisses the winners trophy after he defeated Italy's Matteo Berrettini in the men's singles final on day thirteen of the Wimbledon Tennis Championships in London, Sunday, July 11, 2021. (AP Photo/Kirsty Wigglesworth)

Serbia's Novak Djokovic celebrates his victory over Italy's Matteo Berrettini in the men's singles final match on day thirteen of the Wimbledon Tennis Championships in London, Sunday, July 11, 2021. (AP Photo/Alberto Pezzali)

The Duke of Kent presents Serbia's Novak Djokovic with the winners trophy after he defeated Italy's Matteo Berrettini in men's singles final on day thirteen of the Wimbledon Tennis Championships in London, Sunday, July 11, 2021. At top left is Kate, Duchess of Cambridge. (Pete Nichols/Pool Via AP)

Serbia's Novak Djokovic celebrates winning a point during the men's singles final match against Italy's Matteo Berrettini on day thirteen of the Wimbledon Tennis Championships in London, Sunday, July 11, 2021. (AP Photo/Alberto Pezzali)

Serbia's Novak Djokovic gestures during the men's singles final match against Italy's Matteo Berrettini on day thirteen of the Wimbledon Tennis Championships in London, Sunday, July 11, 2021. (AP Photo/Alberto Pezzali)

Serbia's Novak Djokovic plays a return to Italy's Matteo Berrettini during the men's singles final on day thirteen of the Wimbledon Tennis Championships in London, Sunday, July 11, 2021. (AP Photo/Kirsty Wigglesworth)

Italy's Matteo Berrettini reacts after winning a point against Serbia's Novak Djokovic during the men's singles final on day thirteen of the Wimbledon Tennis Championships in London, Sunday, July 11, 2021. (AP Photo/Kirsty Wigglesworth)

Former Wimbledon champion John McEnroe gives a TV interview ahead of the start of the men's singles final between Serbia's Novak Djokovic and Italy's Matteo Berrettini on day thirteen of the Wimbledon Tennis Championships in London, Sunday, July 11, 2021. (AP Photo/Kirsty Wigglesworth)

Novak Djokovic attends a press conference after winning the men's final against Italy's Matteo Berrettini at the Wimbledon Tennis Championships in London, Sunday, July 11, 2021. (Joe Toth/Pool via AP)

Italy's Matteo Berrettini attends a press conference after being defeated by Serbia's Novak Djokovic in the men's final against at the Wimbledon Tennis Championships in London, Sunday, July 11, 2021. (Joe Toth/Pool via AP)