Leo Rolly Carnando and Daniel Marthin are through to the men's doubles quarter-finals ©BWF

World junior champions in the men's doubles, Leo Rolly Carnando and Daniel Marthin of Indonesia, have upset their fifth seed compatriots, Fajar Alfian and Muhammad Rian Ardianto, on day two of the Badminton World Federation (BWF) Yonex Thailand Open.

In the final match of the night, Carnando and Marthin stole the headlines thanks to their 16-21, 21-17, 22-20 victory in Bangkok.

Other seeds in the men's doubles safely progressed to the quarter-finals, including the South Korean sixth seeds, Choi Solgyu and Seo Seung-jae who thumped Thai duo Weeraphat Phakajarung and Wongsathorn Thongkham 21-9, 21-12.

Indonesian second seeds Mohammad Ahsan and Hendra Setiawan progressed too, as did sixth seeds Lee Yang and Wang Chi-lin of Chinese Taipei.

In the mixed doubles, a couple of seeds crashed out - the most notable being England's seventh seeds Marcus Ellis and Lauren Smith.

The pair were knocked out by Denmark's Mathias Christiansen and Alexandra Bøje by a score of 21-18, 21-18.

Mark Lamsfuss and Isabel Herttrich of Germany had an easier route to the quarter-finals - defeating Hong Kong’s eighth seeds Tang Chun Man and Tse Ying Suet via walkover.

The Hong Kong Institute of Sport advised the pairing to pull out, after a member of German coaching staff had tested positive at Bangkok and it was deemed unsafe to play the pair, who were close contacts.

Fifth seeds Chan Peng Soon and Goh Liu Ying of Malaysia are also through in the competition as are Thailand's top seeds, Dechapol Puavaranukroh and Sapsiree Taerattanachai.

Second seeds, Indonesia's Praveen Jordan and Melati Daeva Oktavianti and fourth seeds from South Korea, Seo Seung-jae and Chae Yujung, are also through.

In the men's singles, second seed Chou Tien Chen of Chinese Taipei and fourth seed Viktor Axelsen of Denmark remain the top seeds in the competition having won their respective matches in straight games.

Fifth and sixth seeds Anthony Sinisuka Ginting and Jonathan Christie of Indonesia are through too in straight games and seventh seed Angus Ng Ka Long of Hong Kong took three games to defeat Wang Tzu Wei of Chinese Taipei.

Eighth seed Malaysian Lee Zii Jia won via walkover against India's Srikanth Kidambi, who pulled out due to a calf strain.

Top women's singles seed Tai Tzu Ying of Chinese Taipei won 21-16, 21-10 against South Korea's Kim Ga Eun, while Olympic champion and fifth seed Carolina Marin thrashed Pornpawee Chochuwong of Thailand 21-8, 21-12.

Eighth seed Michelle Li of Canada, seventh seed An Se-young of South Korea and Thailand's fourth seed Ratchanok Intanon also progressed. 

Finally, South Korean third and fourth seeds in the women's doubles, Lee So-hee and Shin Seung-chan and Kim So-yeong and Kong Hee-yong, are through too after straight game victories.

Their compatriots, sixth seeds Chang Ye-na and Kim Hye-rin are through to the quarter-finals too after a 22-20, 19-21, 21-11 victory over Malaysia's Chow Mei Kuan and Lee Meng Yean.

Seventh seeds Jongkolphan Kititharakul and Rawinda Prajongjai of Thailand are easily through too, as are fifth seeds Greysia Polii and Apriyani Rahayu of Indonesia, completing the final eight line-up.