The favourite and top seed Kento Momota cruised into the last 16 of the Badminton World Federation World Championships with a straight sets victory over Luís Enrique Peñalver in Basel.
Japanese defending champion Momota at eased past his Spanish rival 21-10, 21-7 in Saint Jakobshalle.
China's Dan Lin was a high-profile casualty on day three of the championships, going down 11-21, 21-13, 7-21 against world ranked number 30 HS Prannoy of India.
Prannoy's compatriot, Bhamidipati Sai Praneeth, booked his place in the round of 16 with a 21-16, 21-15 victory against Lee Dong-keun.
Eighth seed Kenta Nishimoto needed three sets to see off Chinese Taipei's Tzu Wei Tang, 25-23, 13-21, 21-16.
Highlights | 2013 World Champion Ratchanok Intanon claims two-game win over 🇹🇭 Thai compatriot Jindapol to advance to the Round of 16 🏸— BWF (@bwfmedia) August 20, 2019
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In the women's draw, top seed Akane Yamaguchi was knocked out by world number 32 Jia Min Yeo of Singapore.
Yeo moved into round three with a 21-14, 21-18 victory.
Thailand's seventh seed Ratchanok Intanon won 22-20, 21-14 against compatriot Nitchaon Jindapol.
Sixth seed Bing Jiao He of China was forced to dig deep to make the third round against Japan's Aya Ohori, winning 21-15, 18-21, 21-12.
Poland's Gregoria Mariska Tunjung joined He in the next round, seeing off Busanan Ongbamrungphan of Thailand 21-14, 21-10.