Novak Djokovic of Serbia wipes the sweat from his face during his semifinal match against Alexander Zverev of Germany at the Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 24, 2025. (AP Photo/Asanka Brendon Ratnayake)

Novak Djokovic of Serbia reacts during his semifinal match against Alexander Zverev of Germany at the Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 24, 2025. (AP Photo/Manish Swarup)

Alexander Zverev, right, of Germany is embraced by Novak Djokovic of Serbia after Djokovic retired in their semifinal match at the Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 24, 2025. (AP Photo/Asanka Brendon Ratnayake)

Novak Djokovic of Serbia plays a forehand return to Alexander Zverev of Germany during their semifinal match at the Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 24, 2025. (AP Photo/Ng Han Guan)

Novak Djokovic of Serbia reacts at a press conference after retiring in his semifinal match against Alexander Zverev of Germany at the Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 24, 2025. (AP Photo/Asanka Brendon Ratnayake)

Novak Djokovic of Serbia reacts during his semifinal match against Alexander Zverev of Germany at the Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 24, 2025. (AP Photo/Manish Swarup)