Kasumi Ishikawa beat South Korea's Seo Hyo-won 4-1 to win the German Open women's singles title on Sunday, while compatriots Mima Ito and Hina Hayata won the women's doubles final.
Ishikawa, Japan's top-ranked player and the world No. 3, beat the 14th-seeded Seo 11-9, 10-12, 11-6, 11-7, 11-6 at OVB Arena in Bremen for her first German Open singles title.
"This is a really lucky place for me. I'm so happy I could win the championship," Ishikawa said.
The 25-year-old, who took the mixed doubles title with Maharu Yoshimura at last year's worlds in Dusseldorf, won German Open doubles gold with Ai Fukuhara in 2010.
Ito and Hayata, bronze medalists at last year's worlds, took down South Korea's Jeon Ji-hee and Yang Ha-eun 3-1 for the doubles crown. Both players earned their second German Open titles after each winning with Miu Hirano previously — Hayata last year and Ito in 2014.
Tomokazu Harimoto and Masataka Morizono were knocked out in the men's doubles quarterfinals by South Korea's Jung Young-sik and Lee Sang-su.