In front of a watching cohort of International Olympic Committee (IOC) Tokyo 2020 Coordination Commission members, 19-year-old Hufumi Abe overcame a field including both the gold and silver medal winners from Rio 2016 to claim a shock under-66 kilograms title.

His younger sister Uta, a World Tour debutant aged 16, had earlier secured under-52kg silver at the Tokyo Metropolitan Gymnasium.

Hifumi, a gold medallist at the Nanjing 2014 Summer Youth Olympic Games, defeated former Astana Grand Prix winner and fellow countryman Yuuki Hashiguchi with a yuko followed by an ippon to underline his claim for a place in the Tokyo 2020 team. 

“I always fight for ippon, this is so important to me," he said afterwards.

"I go forward and give everything in every contest. 

“I want to compete in Europe next year and regularly on the IJF circuit. 

"My first World Championships is my aim and from there I want to become the world number one."

Altansukh Dovdon of Mongolia and Mikhail Puliaev of Russia shared the two bronze medals.

But there was disappointment for Rio 2016 champion Fabio Basile of Italy, who lost his opening bout against another Japanese judoka, Norihito Isoda.

Olympic silver medallist and world champion Baul An of South Korea also suffered a day to forget, finishing down in seventh place.

The second Abe sibling was unable to quite match her brother's achievement as she lost against 24-year-old home star Natsumi Tsunoda after being tapped-out with a juji-gatame.

Japan claimed all four podium positions as Rina Tatsukawa and Ai Shishime shared bronze.

Tsukasa Yoshida retained her Tokyo Grand Slam under-57kg title after winning a marathon 11 minute final against 2014 world champion Nae Udaka.

Momo Tamaoki ensured Japan finished on each podium position by sharing bronze with Sumiya Dorisuren of Mongolia.

Ryuku Nagayama beat Naohisa Takato in the under-60kg final as Russia's Robert Mshvidobadze and South Korea's Choi In-hyuk shared bronze.

The women's under-48kg competition was the only event to elude the hosts as Mongolia's Urantsetseg Munkhbat beat South Korea's Jeong Bo-kyeong in the final courtesy of two shido penalties.

Funa Tonaki and Ami Kondo did each take Japanese bronze medals.

A Coordination Commission delegation including IOC members Alex Gilady of Israel, Habu Gumel of Nigeria, Nicole Hoevertsz of Aruba and Irina Szewinska of Poland and Association of Summer Olympic International Federations President Francesco Ricci Bitti were present for the finals.

Vizer had formally been a member of the inspection panel before resigning at the same time as he stood-down as President of SportAccord last year.

Ricci Bitti has since replaced him.

“It is always a great honour for our sport to come back to Japan and this year to conclude and launch a new Olympic cycle at the same time," Vizer said.

"It was also our great pleasure to welcome the IOC Coordination Commission of the Tokyo 2020 Olympic Games, on the occasion of this first day of competition. 

"I want to underline the motivation and enthusiasm of all the athletes who participated today and who are now starting a new adventure towards Tokyo 2020."

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