HONG KONG, HONG KONG - NOVEMBER 17: Tai Tzu Ying of Taipei retires in the match against Nozomi Okuhara of Japan during the semi-final of Women's Single on Day 5 of Yonex Sunrise Hong Kong Open 2018 at Hong Kong Coliseum on November 17, 2018 in Hong Kong, Hong Kong. (Photo by On Man Kevin Lee/Getty Images)
