Opening the home nation’s gold medal rush at the Maruzen Intec Arena was world silver medallist Funa Tonaki, who beat Mongolia’s Urantsetseg Munkhbat in the women’s under-48 kilograms final. 

Munkhbat, a former world champion, showed off her ne-waza prowess in the earlier rounds but made a mistake on the ground in the final when she miscalculated a turnover.

Tonaki took full advantage as she applied a mune-gatame for 20 seconds to take top honours in less than a minute.

Victory secures her second IJF Grand Slam title and gives her the edge over Munkhbat in their head-to-head series, which now stands at 4-3.

Japanese athletes triumphed in the bronze medal contests with Hiromi Endo surging past France’s Melanie Clement in 44 seconds and Ami Kondo defeating South Korea’s Kang Yujeong.

There was also success for Japan today in the women’s under-52kg category as teenage world champion Uta Abe won her third IJF Grand Slam crown to remain undefeated since 2016.

The 18-year-old squared off against team-mate and Asian Games winner Natsumi Tsunoda in the final and avenged her only loss on the IJF World Judo Tour, which came in the 2016 Tokyo Grand Slam gold medal match.

Abe went forward and pressed world number nine Tsunoda with a barrage of attacks, but the latter proved to be very difficult to throw and held off her superstar colleague to force the final into golden score.

The contest was called to a halt after 57 seconds of additional time when Tsunoda was penalised for not taking a grip as her rival improved her winning run to 33 consecutive contests and her last seven events.

"I feel relieved to win," Abe said.

"I had lost against Tsunoda three times and needed to win today to push myself towards the Tokyo 2020 Olympic Games."

The first bronze medal match was won by Japan’s Ai Shishime, who overcame compatriot Chishima Maeda by ippon.

France’s Amandine Buchard pipped South Korea’s Park Da Sol to the podium by coming out on top in the second.

Japan’s domination extended to the men’s side of competition with world bronze medallist Ryuju Nagayama claiming his fifth IJF Grand Slam crown and the most important title of his career in the under-60kg category.

Nagayama defeated European under-23 champion Yago Abuladze of Russia by a single score in the final. 

Russia’s surprise package, who was ranked number 165 in the world at the start of the day, looked at home on his IJF Grand Slam debut as his unorthodox style carried him through to the final.

A waza-ari from Nagayama after 22 seconds was the difference with the victor increasing his lead at the top of the under-60kg rankings.

South Korea’s Kim Won Jin was one of the two bronze medallists after beating Brazil’s Eric Takabatake.

He was joined on the third step of the podium by Japan’s Yuma Oshima, who defeated compatriot Toru Shishime.

World champion Naohisa Takato of Japan was beaten by Kim in the preliminaries, bringing an end to a 35-fight winning-streak coming into his home IJF Grand Slam.

In the men’s under-66kg category, Hohhot Grand Prix winner Jōshirō Maruyama of Japan stole the show as he outshone two-time reigning world champion, and fellow countryman, Hifumi Abe.

Maruyama overcame the seven-time IJF Grand Slam winner in the last contest of day one with a yoko-tomoe-nage effort after 63 seconds of golden score.

Russia’s Aram Grigoryan beat Japan’s Taroh Fujisaka in the first bronze medal match before Mongolia’s Baskhuu Yondonperenlei defeated Russia’s Islam Khametov in the second.

Competition in Osaka is due to continue tomorrow. 

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