山口茜
In 2019, she reached the quarterfinal stage of Malaysia Masters, losing to the same opponent of last year and arch-rival Ratchanok Intanon in straight games. In March, she advanced to the final of All England Open for the third straight time, however she unexpectedly lost to the Chinese Chen Yufei, after 11 straight victories over her. She came back and claimed back to back titles at Malaysia Open and Singapore Open; beating Japanese Akane Yamaguchi and Nozomi Okuhara respectively in finals in two straight games. In July, she was unable to defend her title at the Indonesia Open, after defeated in the semi-finals to Akane Yamaguchi. Her Jinx at World Championships continued further after she lost to P. V. Sindhu of India in the quarter-finals in 3 games 21–12, 21–23, 19–21. This was her 5th Straight quarterfinal loss at the World Championships.