The Frenchman, a 10-time world champion who has incredibly not been beaten since 2010, made his highly anticipated return to the tatami in the Canadian city after not seeing action since November 2017.

Thirty-year-old Riner has now set his sights on a third consecutive Olympic title in the men's over-100 kilograms class at Tokyo 2020.

He defeated Japan's Hisayoshi Harasawa in today's final at the Maurice Richard Arena, a repeat of the Rio 2016 Olympic gold medal bout which also went the way of Riner.

The contest went to golden score after the two judoka shared four shido penalties between them, and it was the Frenchman who made the decisive move as he flipped Harsawa for a waza-ari.

He also needed golden score to defeat under-100kg Olympic champion Lukas Krpalek of the Czech Republic in the semi-finals, who has moved up the weight divisions. 

Riner eventually threw his rival but only after three nervy minutes of the extra period.

His winning streak now stands at a remarkable 148 matches.

"It was no easy comeback, it was a long period," said Riner as the Grand Prix concluded today.

"Today I won but I competed against some fine opponents. 

"It was no walk in the park."

Krpalek recovered to win bronze alongside Brazil's David Moura.

In today's other weight divisions Japan confirmed their dominance of the sport with three more gold medals to end the event with seven.

Reigning world champion Shori Hamada won the women's under-78kg class as she threw Russia's Aleksandra Babintseva for ippon.

Ecuador's Vanessa Chala and Germany's Maike Ziech won bronze.

A second women's gold arrived for Japan in the heavyweight over-78kg competition as Sarah Asahina, another reigning world champion, defeated Israel's Raz Hershko via ippon.

Bronze medals went to Japan's Nami Inamori and Melissa Mojica of Puerto Rico.

In the men's under-90kg division, Japan's Olympic champion Mashu Baker struck gold after countering a move from American Colton Brown for waza-ari.

Rafael Macedo of Brazil and Slovakia's Milan Randl collected the bronzes.

Hosts Canada were disappointed in the final of the men's under-100kg as Shady Elnahas was beaten by Egypt's top seed Ramadan Darwish who connected for ippon.

Canada also won a bronze through Kyle Rees as he shared the third step of the podium with Brazil's Leonardo Goncalves.

The next competition on the IJF World Tour is the Budapest Grand Prix which begins on Friday (July 12).

Watch the action on Judo TV.