Reigning world champion Nozomi Okuhara pulled out of the ongoing badminton national championships on Wednesday, citing a knee injury.
Okuhara, who beat archrival Pusarla Sindhu of India in the final for the women's world singles crown in August, withdrew after winning a point in the first game of her first-round match at Komazawa Gymnasium in Tokyo.
"I'm not in shape to compete in a tournament. I decided (to withdraw) this morning. It was a tough decision but I had to do this to keep my eyes on the Tokyo Olympics. I promise to come back stronger," she said.
"My manager and coach respected my wish to stand on the court," she said, when asked why she didn't withdraw before the Nov. 27-Dec. 3 tournament got under way.
Okuhara injured her right knee at the Japan Open Superseries tournament in September and though she says the condition is improving, she has not been able to hold on-court training sessions.
The 22-year-old said she has not given up hope of competing in the Dec. 13-17 Superseries Finals in Dubai that feature the top eight players or pairs in each discipline.