TOKYO - World champion Ratchanok Intanon was forced out of the Japan Open suffering lower back pain, organisers said on Wednesday.
Ratchanok.
The back problem also sidelined the 18-year-old Thai from the China Masters last week. She has not played since winning the world title last month.
China's world No.1 Li Xuerui, who lost to Ratchanok in the women's singles final at the world championships, also pulled out of the tournament with a sore knee.
On the men's side, world No.2 Chen Long of China, suffered a shock defeat in the first round yesterday going out 24-22, 21-16 to Kazuteru Kozai of Japan, ranked 287th in the world.