Sindhu, a double Olympic medallist, beat Denmark’s Julie Dawall Jakobsen 21-15, 21-18 in women’s singles, while London Olympics bronze medallist Saina, who had suffered a groin injury at Uber Cup final, retired after lagging 11-21, 2-9 against Sayaka Takahashi of Japan.
Sindhu, seeded third, will clash with another Dane Line Christophersen next.
Lakshya had a good day in office as he defeated Ireland’s Nhat Nguyen 21-10, 21-16 to set up a clash against Singapore’s Loh Kean Yew next in men’s singles.
Sourabh Verma also made a positive start, outwitting Brazil’s Ygor Coelho 22-20, 21-19 in 43 minutes. He will meet Japan’s Kenta Nishimoto in the second round.
His younger brother Sameer, who played his opening round on Tuesday, will face Indonesia’s Shesar Hiren Rhustavito.
However, it was curtains for Kidambi Srikanth, Parupalli Kashyap and HS Prannoy in men’s singles.
Srikanth, the Rio Olympic quarterfinalist, played his heart out to match top seed Kento Momota and also held a two-point lead towards the end of the decider but ended up losing the men’s singles second round tie 18-21, 22-20, 21-19 in 79 minutes.
Kashyap went down fighting 17-21, 21-17, 11-21 to Brice Leverdez of France, while Prannoy lost 11-21, 14-21 to Chinese Taipei’s fourth seed Chou Tien Chen.
Men’s doubles pair of MR Arjun and Dhruv Kapila, however, gave some cheers to the Indian camp, beating Ireland duo of Joshua Magee and Paul Reynolds 21-13, 21-7 to reach the next round.
Srikanth, who had lost to Momota last week also at Denmark Open, produced a much better display here and came agonisingly close to outwitting the two-time world champion, only to fall short in the end.
Mixed doubles pair of Satwiksairaj Rankireddy and Ashwini Ponnappa, the world number 24 pair, beat Denmark’s Mathias Thyrri and Mai Surrow 21-19, 21-15 in 37 minutes.
They will face second seeded Indonesian pair of Praveen Jordan and Melati Daeva Oktavianti next.
Top seeded Korean pair of Lee Sohee and Shin Seungchan beat Ashwini and N Sikki Reddy 21-16, 21-17 in a women’s doubles match.
Earlier, Srikanth put up a brave effort but it wasn’t enough to outwit the former world no 1 Momota.
Srikanth raced to a 4-0 lead but Momota clawed back to level the scores. He again moved to a 8-5 advantage only to see the Japanese eke out a slender 11-10 lead at the break.
After the break, Momota kept his nose ahead despite Srikanth snapping at his heels and drawing parity at 18-18 at one stage.
The second game was even more engrossing as the lead exchanged hands many times before Momota managed to take a 11-9 advantage at the breather.
The Japanese held two game points but Srikanth staged a superb fight back and reeled off four straight points to roar back into the contest.
The decider started with a similar intensity with Srikanth heading to a 9-6 advantage but Momota made it 11-10 at the break.
The Indian moved to 19-17 but a couple of errors cost him dearly.
India’s doubles Olympic medallist Sindhu along with other Indians will compete later in the day.