Gviniashvili, who turns 20 tomorrow and will then be too old for junior competition, defeated Spanish opponent Nikoloz Sherazadishvili in the final via ippon for gold.

"I waved goodbye to everyone because this was my last time to compete as a junior," he said.

"It’s my birthday tomorrow so I’ll be celebrating with my team mates tonight.”

The Georgian, who won his final in less than 43 seconds, is currently ranked fifth in the senior standings and won the second biggest senior competition of the year, the World Masters, in May.

Bronze medals went to  Junior European Championships bronze medallist Piotr Kuczera of Poland, who beat German David Tekic, and Azerbaijan's Firudin Dadashov who was too strong for Russian Mikhail Igolnikov.

Both victories were decided by ippon with Dadashov winning in just 40 seconds.

Elsewhere in the United Arab Emirates' capital, Japan won their fifth world title of the Championships as Nami Nabekura took home women's under 63kg gold.

Last year's runner-up saw off Russian Diana Dzhigaros after landing two waza-aris in the bout.

Lara Reimann of Germany held down 18-year-old former Cadet World Championships bronze medallist Lubjana Piovesana of Great Britain for an ippon to claim bronze, but the defeated country weren't to be denied a medal as Lucy Renshall defeated Greek judoka Elisavet Teltsidou via waza-ari to also earn a place on the podium.

In the women's under 70kg category, Hungarian Szabina Gercsák, the 2014 Nanjing Youth Olympic Games winner, was the golden girl after a final win via a single shido against Japan's Remi Aoyagi.

Natascha Ausma of The Netherlands defeated compatriot Sanne Van Dijke for the first bronze with yuko scores, with the second going to Germany's Lisa Dollinger who proved too strong for team-mate Giovanna Scoccimarro in another one-country affair, via ippon.

There was Dutch delight in the men's under 81kg division thanks to Frank De Wit who defeated Cadet Asian Championships winner Sotaro Fujiwara of Japan with a yuko score.

Bronzes were awarded to Ukraine's Viktor Makukha, who dismissed Lee Moon Jin with an ippon, and Cuba's Pan American Games silver medallist Ivan Felipe Silva Morales who was too strong for Mongolian Bat-Erdene Bandikhuu on shido penalties.

To watch the latest action on Judo TV click here.

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