Olympic champions Ayaka Takahashi and Misaki Matsutomo captured their second badminton's World Tour Finals championship in women's doubles on Sunday.
Takahashi and Matsutomo, the top seeds, beat Lee So Hee and Shin Seung Chan of South Korea 21-12, 22-20 to win their second tour finals title and their first in four years.
Earlier, Kento Momota and Nozomi Okuhara each crashed out in the finals of the men's and women's singles, respectively.
Momota, the world's top-ranked men's player, lost to second-ranked Shi Yuqi of China 21-12, 21-11.
"I became timid and stayed that way, but that was because he began dictating the action," Momota said. "Today my opponent was superior to me in every area."
World No. 5 Okuhara fell to sixth-ranked Indian P.V. Sindhu, 21-19, 21-17. The 23-year-old Japanese, who beat Sindhu to become world champion in 2017, failed in her bid to regain the tour final championship she last won three years ago.
"The accuracy of my shots was way too poor. I could never get the initiative," said Okuhara, who has recently been hobbled by shoulder and knee injuries.
In the men's doubles final, Japan's Hiroyuki Endo and Yuta Watanabe lost 21-15, 21-1 to China's Li Junhui and Liu Yuchen.