Looking for her first title this season, world No 7 Saina hardly broke a sweat as she outplayed Indonesia's Bellaetrix Manuputty 21-14, 21-16 in 34 minutes.
The 23-year-old Indian will meet Thailand's Porntip Buranaprasertsuk on Thursday.
World No 10 Sindhu lost 16-21, 17-21 to second seed Ratchanok Intanon of Thailand in another women's singles match, while Kashyap suffered a 14-21, 10-21 defeat against China's Zhengming Wang in the men's singles.
Rising shuttler K Srikanth also crashed out in the opening round of the men's singles, losing 18-21, 14-21 to world No 1 Lee Chong Wei of Malaysia.
India's men's doubles pair of Pranaav Jerry Chopra and Akshay Dewalkar, too, suffered similar fate, losing 18-21, 19-21 to the top seeded Indonesian combo of Mohammad Ahsan and Hendra Setiawan.
The Indian pair of Manu Attri and Sumeeth Reddy B was also sent packing 9-21, 15-21 by Russia's Vladimir Ivanov and Ivan Sozonov in 26 minutes.
Saina, seeded seventh, was far superior than her world No 10 opponent, scoring as many as 14 smash winners.
The Olympic bronze medallist had beaten Bellaetrix at the Indian Open in April.
Saina raced away with the first game after opening up a 5-0 lead.
In the second, too, she led 6-3 before Bellaetrix staged a strong recovery to level at 14. However, Saina stepped up the paced and reeled off four straight points and then never looked back to take the match.
The Indian ace will have to be careful in the next round against Porntip even though she enjoys a 6-0 win-loss record over the Thai.
The last time Saina and Porntip faced each other was in the World Championships in China and it was a three-game affair.
Image: Saina Nehwal
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