South Korea’s An Se-young and France’s Christo Popov triumphed at badminton’s year-end BWF World Tour Finals in Hangzhou on Sunday as hosts China suffered dual disappointment. In the women’s final, An defeated China’s defending champion Wang Zhiyi to claim her 11th singles title of the year, equalling the record of Kento Momota of Japan. Olympic champion An had to overcome cramp in the final game of a marathon match lasting 96 minutes, before wrapping up a 21-13, 18-21, 21-10 victory. “It seems...