Fourth-seeded Minh needed just 32minutes to see off the young Japanese player, dominating the game formost part except in the first set when he allowed Sonoda to restoreparity at 17-17 after trailing 9-15. But the Vietnamese ace reeled offour consecutive points to take the first set in 15 minutes.
Inthe quarter-finals, Minh will face his first real challenge againstChina's sixth-seeded Du Pengyu, who went through a tense three-setteragainst unseeded Darren Liew of Malaysia in the third round.
Inspite of beating Du in both their previous meetings – the Yonex AllEngland Open Badminton Championships 2011 and 2010 Korean Super Series -Minh is expected to have his work cut out for him this time.
Ifhe is able to make it to the semi-finals, Minh could run into Chinesetop-seed Lin Dan, who cruised into the quarterfinals after making lightwork of three previous rounds.
In the men's doubles, Vietnameseduo Bui Bang Duc and Dao Manh Thang bowed out of the tournament afterlosing in two sets to the Indonesia pair, Alvent Yulianto Chandra andHendra Aprida Gunawan./.