The 21-year-old Japanese star, who followed gold at the 2013 World Championships in Rio de Janeiro with bronze at last year's event in Chelyabinsk, won an entertaining final with world bronze medallist Orkhan Safarov of Azerbaijan, triumphing courtesy of having conceded just one penalty point in comparison with his opponent's two. 

Uzbekistan's Sharafuddin Lutfillaev and Mongolian world number one Boldbaatar Ganbat of Mongolia claimed the two bronze medals. 

A second Japanese gold was won by under 63kg female fighter Miku Tashiro who, in the absence of French world number one Clarise Agbegenou, dominated nonetheless against her European opponents, scoring an early yuko against Austria's Kathrin Unterwurzacher before immobilising her with an ippon in the last 10 seconds. 

It marked arguably the biggest success of 21-year-old Tashiro's career so far, following on from a World Championship bronze last year and gold at the inaugural Summer Youth Olympic Games in Nanjing. 

Japanese fighters did not have it all their own way in the Moroccan capital, with Mongolia showing their traditional prowess in the lighter events and Russia demonstrating how they have one of the strongest all round squads in the world. 

World number one and reigning Asian Games champion Urantsetseg Munkhbat tasted victory in the under 48kg division, getting the better of Argentina's third ranked Paula Pareto in the final with an armlock for ippon within the first minute of their final bout. 

A second Mongol title came in the under 57kg event, where Asian Games bronze medallist Sumiya Dorjsuren, a three-time reigning world champion in sambo, overcame Helene Receveaux of France in the final as Japan's Nae Udaka and Romania's Corina Caprioriu each won battles for bronze.

Natalia Kuziutina in the women's under 52kg event and Denis Iartcev at under 73kg were the two Russian champions on the first of two days of action in the Palace of Sport, beating Japan's Yuki Hashimoto and Georgia's Nugzari Tatalashvili in their respective finals.

The only athlete to break the Mongol-Russian-Japanese dominance was Ukraine's Georgii Zantaraia, who beat Belorussian opponent Dzmitry Shershan in the under 66kg final. 

Action is due to continue tomorrow with the remaining seven divisions, at under 70kg, under 78kg and over 78kg for women and at under 81, under 91kg and under 100kg and over 100kg for men.

Watch the latest action on Judo TV here.

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