Graf had been struggling with a knee injury in the early weeks of the year, but showed no ill effects of the problem as she secured four straight ippons to reach the gold medal bout, where she met Tokyo Grand Slam winner Arai Chizuru,

Their encounter turned out to be a brief one as Graf threw her Japanese opponent to achieve another ippon, after just 65 seconds.

Colombia’s Yuri Alvear had fallen at the hands of Graf in the semi-final but joined her on the podium after beating Israel’s Linda Bolder with a waza-ari in her bronze medal bout.

Laura Vargas Koch triumphed over Britain’s Sally Conway in the same manner to give the host nation their first medal of the Grand Prix.

The only other women’s competition today saw Slovenia’s Tina Trstenjak live up to her status as the current world champion by producing a series of commanding displays in the under 63kg category.

She benefited from Britain’s Alice Schlesinger receiving two shido penalties at the start of their final, before pinning her opponent down for 20 seconds to earn a match winning ippon.

Russia’s Ekaterina Valkova surprisingly overcame 2013 world champion Yarden Gerbi of Israel with an ippon in their bronze medal tie and Mongolia’s Munkhzaya Tsedevsuren claimed a shido penalty win over Sweden’s Anna Bernholm to secure the final podium spot.

There was success for another world champion in the men’s under 73kg division, as Japan’s Ono Shohei successfully defended his Düsseldorf title.

The 24-year-old defeated the world number one Rustam Orujov of Azerbaijan with a waza-ari, to show that he will be the man to beat come Rio 2016. 

Olympic champion Lasha Shavdatuashvili of Georgia also secured podium spot, beating Slovenia’s Rok Draksic with an ippon.

South Korea’s An Changrim achieve the same feat in his tie against Mongolia’s Narankhuu Khadbaatar.

German gold medal hopes were dashed in the final bout of the day as Sven Maresch fell to Belgium’s Joachim Bottieau in the under 81kg category.

The 26-year-old triumphed at the venue in 2015 and repeated the trick, earning a waza-ari win over rival.

Bulgaria’s Ivaylo Ivanov defeated Mongolia’s Uuganbaatar Otgonbaatar on shido penalties to clinch the first bronze, while a waza-ari and yuko saw Georgia’s Giorgi Papunashvili claim the other medal against Germany’s Dominic Ressel.

The Grand Prix is due to conclude tomorrow with the women's under 78kg and over 78kg and the men's under 90kg, under 100kg and over 100kg. 

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