While a vaccine rollout may have eased some of the emotional burden for Japanese athletes, many remain torn between wanting to live out their Olympic dreams and potentially playing a role in an unfolding public health disaster.

Japan relaxed emergency coronavirus restrictions in Tokyo and eight prefectures on Monday and members of its delegation started vaccinations from June 1, but athletes still have serious concerns over whether the games can be staged safely.

"I'm not 100% optimistic yet," men's tennis star Kei Nishikori said, voicing a thought likely shared by many other Olympic athletes.