As players took to the court at the Badminton World Federation (BWF) the top seeds are through, despite dropping games in the first round.
In the men’s singles tournament, top seed and world champion Kento Momota is through to the second round after beating China’s double Olympic gold medallist Lin Dan in three games, 21-19, 12-21, 21-15 at the Hong Kong Coliseum.
The Japanese player is seeking to add another title to his four victories this year.
The second and third seeds, though, are out of the BWF World Tour Super 500 event.
China’s second seed Shi Yuqi retired before completing the first game to send through home favourite, Lee Cheuk Yiu, leading 11-3 at the time.
Chinese Taipei's Asian Games silver medallist Chou Tien Chen, the third seed, was beaten 8-21, 23-21, 22-20 by South Korea’s Lee Dong Keun,
In the women’s event, top seed and defending champion Tai Tzu Ying is through, despite a shaky start which saw the three-time winner of this event drop the first game against Hong Kong’s Yip Pui Yin before recovering to win 16-21, 21-8, 21-14.
Spain's world and Olympic champion Carolina Marin found things easier, cruising through her first round match in straight games.
The fifth seeded Marin defeated Indonesia’s Busanan Ongbamrungphan, 21-10, 21-18 to stay on target to meet Tai in the quarter-final if both get that far.
The second and third seeds were also eliminated in the men’s doubles competition.
Top seeds Marcus Fernaldi Gideon and Kevin Sanjaya Sukamuljo of Indonesia safely progressed 21-14 21-15 over Japan’s Hiroyuki Endo and Yuta Watanabe but the other top pairings fell.
China’s second seeds Li Junhui and Liu Yuchen were beaten 21-12, 21-15 by Lee Jhe-Huei and Lee Yang from Chinese Taipei.
Third seed compatriots Liu Cheng and Zhang Nan lost 21-12, 21-15 to Goh Shem and Tan Wee Kiong.
In the women’s doubles, the top two seeds come from Japan and advanced into the second round.
Yuki Fukushima and Sayaka Hirota defeated Hong Kong’s Lui Lok Lok and Tsang Hiu Yan 21-10, 21-9.
Despite dropping the first game, second seeds Misaki Matsutomo and Ayaka Takahashi recovered to win over India’s Ashwini Ponnappa and Reddy Sikki 18-21, 21-10, 21-8.