After a semi-final finish at the India Open last week, Saina had an easy opener at the US $550,000 tournament, beating Nitchaon Jindapol 21-16, 21-7 in 30 minutes and registering her sixth victory over the Thai girl in the process.
The 26-year-old Indian, seeded third, will next meet Korea's Bae Yeon Ju, who ended Sindhu's campaign at the India Open last week.
Seeded sixth, Sindhu beat He Bingjiao of China 21-16, 21-17 in 40 minutes to avenge her defeat in the 2015 Indonesian Masters and 2016 Swiss Open.
The two-time bronze medallist at the World Championships will next meet Korea’s seventh seed Sung Ji Hyun, who had lost to Saina at the India Open last week.
However, in the men's singles, Rio Olympics hopefuls H S Prannoy and K Srikanth failed to cross the opening hurdle.
Srikanth, who failed to defend his title at the India Open after going down to China's Tian Houwei in the opening round, continued to find the going tough in Super Series events.
His 3-1 record against Boonsak Ponsana accounted for nothing as he lost 21-23, 21-9, 10-21 to the Thai shuttler in 53 minutes.
Prannoy, who clinched the Swiss Open last month, fought hard before going down 19-21, 20-22 to India Open champion Kento Momota of Japan, seeded third in this tournament.
Prannoy had lost in the opening round in the India Open as well.
Image: Saina Nehwal
Photograph: Christopher Lee/Getty Images for Falcon
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