The sixth seed Indian, Saina overcame Japan's Nozomi Okuhara 21-14 21-19 in a 39-minute opening match, while world number 12 Kashyap recorded his fourth victory over the eighth ranked Thai Boonsak Ponsana when he beat him 22-20 21-15 in men's singles opening round match that lasted 46 minutes.
Olympic Bronze medallist Saina relied on her net game to outclass Nozomi as she registered 19 net winners compared to 11 by the Japanese. The 23-year-old Indian will next take on China's Sun Yu in the prequarterfinals.
In the second game, Saina enjoyed a 10-6 lead but Nozomi reeled off four points to catch up with the Indian. What ensued next was a tough battle for supremacy but it was the world number seven Indian who had the last laugh in the end.
Kashyap matched his higher ranked rival with his smashes and outdid him in net play to earn a place in the second round, where he will meet Japan's Kento Momota tomorrow.
In the second game too, Boonsak held an early 3-0 lead but Kashyap soon surged ahead at 6-4. The lead changed hands till 14-14, before the Indian once again raised his game and broke free, capturing four points and three points on the trot.