Novak Djokovic (L) of Serbia and Dominic Thiem of Austria pose with the trophy during the awarding ceremony after the men's singles final at 2020 Australian Open in Melbourne, Australia on Feb. 2, 2020. (Photos: Xinhua)

Novak Djokovic (C) of Serbia poses with ball kids during the awarding ceremony after the men's singles final against Dominic Thiem of Austria at 2020 Australian Open in Melbourne, Australia on Feb. 2, 2020.

Novak Djokovic of Serbia celebrates during the men's singles final against Dominic Thiem of Austria at 2020 Australian Open in Melbourne, Australia on Feb. 2, 2020.

Dominic Thiem of Austria returns the ball during the men's singles final against Novak Djokovic of Serbia at 2020 Australian Open in Melbourne, Australia on Feb. 2, 2020.

Novak Djokovic (L) of Serbia and Dominic Thiem of Austria pose with the trophy during the awarding ceremony after the men's singles final at 2020 Australian Open in Melbourne, Australia on Feb. 2, 2020.