Badminton’s world No 4 beat compatriot Busanan Ongbamrungphan for her second title here 12 months ago and is determined to reign again from July 10-15 at the Nimibutr National Stadium.

After 34 years, the tournament has been upgraded from World Tour 300 to Super 500 SuperSeries level. As a result, the field will be tougher tanks to the presence of elite players including world No 2 Akane Yamaguchi and current world champion Nozomi Okuhara, members of the Japan Uber Cup team who beat Thailand in the final last month.

The other strong contender for the women’s singles title is India’s world No 3 Pusarla V Sindhu.

“It will be very tough to defend the title with several top players signing on to play. I hope my fellow Thais and I will summon top form to win at home,” said Ratchanok, who will open her campaign against Gregoria Mariska Tunjung of Indonesia. Thai Nos 2, 3 and 4 – Nitchaon Jindapol, Busanan and Pornpawee Chochuwong – are also in action.

On the men’s side, Thai hopes Khosit Phetpradab, Suppanyu Avihingsanon and Kantaphon Wangcharoen will test their mettle against the world’s best, including world No 3 Shi Yuqi and 2016 Olympics gold medallist Chen Long of China.

Thai badminton chief Khunying Patama Leeswadtrakul is confident of more local success, after the last three home tournaments – the Thailand Masters 2017 and 18 and Thailand Open 2017 – were won by Thai women.