Novak Djokovic wrestled with rare feelings of being hopelessly out of shape during a workout with retired sumo professionals on Monday.
The 32-year-old Serb, who is in Tokyo to play in the Japan Open Tennis Championships, visited a traditional dohyo or a sumo ring to watch the wrestlers during their morning practice.
Djokovic tried to push his counterpart as much as he could without practically no results.
"I felt I'm out of shape (for sumo) a little bit ... with a few more kilos, I'll be ready to compete. Probably three times as much as I have right now would be the right measurement for me to compete," Djokovic joked.