Yamaguchi, who beat Chen in a three-set thriller in the world championships final last Sunday, fought back from one set down and 14-9 behind in the third set to win 15-21, 21-16, 24-22.
The Japanese star has beaten Chen five times in a row and improved her record to 15 wins and eight losses.
“I tried to do something different from what I did last week. It worked in the first set. But in the second and third sets, Yamaguchi was faster and more confident,” Chen said.
Yamaguchi, who took the title when the Japan Open was held last time in 2019, will fight for the crown against South Korea’s An Seyoung, who upset second seed Tai Tzu Ying of Chinese Taipei 21-12, 13-21, 21-14.
Team China, the biggest winner at the world championships with two gold, one silver, and two bronze medals, lost five of six matches on Saturday and only one pair of men’s doubles shuttlers got through to the finals, reports Xinhua.
In the men’s singles, Shi Yuqi, playing his second tournament since coming out of a 10-month suspension, went down to fourth seed Chou Tien Chen of Chinese Taipei 15-21, 21-19, 21-12. Chou will take on Kenta Nishimoto, who edged past Anders Antonsen of Denmark 22-20, 21-19.
Zheng Siwei and Huang Yaqiong, who have won seven mixed doubles titles this season, had their winning streak of 38 matches snapped as they lost to archrivals Yuta Watanabe and Arisa Higashino 21-17, 12-21, 23-21.
Wang Yilyu and Huang Dongping, who shocked Zheng and Huang in the Tokyo Olympic final last year, were beaten by Dechapol Puavaranukroh and Sapsiree Taerattanachai of Thailand 21-18, 21-18.
Top-seeded Chen Qingchen and Jia Yifan, who won the women’s doubles world title for the third time last week, lost a close match to Baek Hana and Lee Yulim of South Korea 12-21, 21-18, 21-19.
China’s only representatives in the finals are Liang Weikeng and Wang Chang, who beat South Korean duo Choi Solgyu and Kim Wonho 21-16, 21-16.
Liang and Wang, who just started to play together in May, will vie for the title against seventh-seeded Kim Astrup and Anders Skaarup Rasmussen of Denmark, who saw off South Korea’s Kim Gijung and Kim Sarang 13-21, 21-18, 21-11.
–IANS
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