Japan's Rio Olympic judo gold medalists believe their country has reclaimed its rightful place as the sport's world No. 1, but warned the pressure to succeed at the 2020 Tokyo Games will be enormous.

"Our results in Rio have increased expectations on judo toward the Tokyo Olympics," men's 73-kg champion Shohei Ono, one of three Japanese judo gold medalists at the Rio Games, told an audience at the Foreign Correspondents' Club of Japan in Tokyo on Tuesday.

"It's natural that Japan will win medals. That is the environment that has been created. Of course being the host country will add a pressure incomparable to what we experienced in Rio. But in the time before then, I'd like to keep setting small goals and hopefully that will lead to one big achievement in four years' time."