Haruka and Megumi Tachimoto struck gold at the Paris Judo Grand Slam on Sunday, winning the women's 70-kg and 78-kg divisions, respectively.
Haruka, the younger of the Tachimoto sisters and ranked fourth in the weight class, stunned France's Lucie Decosse by decision 2-1 after extra time, denying the two-time defending world champion what would have been her eighth title in Paris.
"The biggest strength I've got is my heart," Haruka said after beating Decosse, the women's judoka of the year and the gold-medal favorite at this summer's London Olympics.
"I fought today not willing to give anyone an inch. I felt like I'd been gaining on (Decosse) recently. I stayed positive and confident throughout the match," she said.
Megumi also won by decision in the final, 3-0, over Russia's world bronze medalist Elena Ivashchenko after the golden score.