The world No 8 Ratchanok eliminated the world No 2 21-15 21-12 in just 38 minutes, avenging her last two straight defeats to the Japanese last year in World Tour Finals in China and Hong Kong Open.

The Thai ace will play long-time rival Akane Yamaguchi who leads her 11-9 in their head-to-head record. The Thai however won their last meet in Hong Kong last year.

However, Thai duo Bodin Isara and Maneepong Jongjit had to retire during the men’s doubles semi-final match with top seeded Takeshi Kamura and Keigo Sonoda of Japan after losing the first game 11-21.