After losing the first game, the 24-year-old Indian rebounded strongly to clinch a 15-21, 21-13, 21-13 win over Wan Ho in a gruelling second-round clash that lasted almost an hour.
Former world No. 1 Kidambi Srikanth's wretched run continued as he went down 6-21, 17-21 to fellow-Indian Ajay Jayaram, diminishing his hopes of qualifying for the Tokyo Games.
Besides Srikanth, the other players withdrawn are Ashwini Ponnappa, Ritika Rahul Thkar, Treesa Jolly, Mithun Manjunath, Simran Aman Singh and Khushi Gupta.
If Saina manages to go past Okuhara, the Indian might run into fourth seed Carolina Marin, who is placed in her half of the draw.
Star Indian shuttlers PV Sindhu and Kidambi Srikanth will look to arrest their slump in form when they begin their campaign at the Australia Open badminton tournament in Sydney on Tuesday.
Kashyap, a Commonwealth Games champion, was trailing 8-14 in the third game when he chose to retire after pulling his calf muscle.
Fresh from their Korea Open triumph, Satwiksairaj Rankireddy and Chirag Shetty will look to continue their dream run.
On Wednesday, Commonwealth Games bronze medallists Ashwini Ponnappa and N Sikki Reddy, seeded eighth, scraped past the Denmark duo of Amalie Magelund and Freja Ravn 21-9, 17-21, 21-19 in the women's doubles.
Prime Minister Narendra Modi and cricket icon Sachin Tendulkar, among others, lavished praise on Kidami Srikanth for claiming the Australian Open title with a stunning win over reigning Olympic and world champion Chen Long.
Sindhu, a 2019 World Champion, lost 14-21, 21-15, 14-21 to Zhang in a match that lasted 55 minutes.
A summary of sports events and persons who made news on Thursday
Summary of sports events and persons who made news on Wednesday
The top-16 in the world by April-end will make the cut for the Olympics.
Kidambi Srikanth is against any drastic changes in the scoring system being contemplated by the world body.
H S Prannoy stunned World No 10 Kanta Tsuneyama while ace Indian women shuttlers PV Sindhu and Saina Nehwal also sailed into the second round of the Malaysia Masters, in Kuala Lumpur, on Wednesday. World Championships bronze-medallist B Sai Praneeth and the seasoned Kidambi Srikanth, though, bowed out of the men's singles events.
However, four of her compatriots, including double Olympic medallist P V Sindhu and World Championships silver winner Kidambi Srikanth, progressed to the quarterfinals of their respective events.
Kidambi Srikanth's experience at the Thailand tour has been far from pleasant
Kidambi Srikanth might be inching towards the coveted World No 1 ranking after his record-equalling Super Series win in Paris but he says he does not want to lose sleep over chasing it.
Kidambi Srikanth entered the final of the $120,000 Swiss Grand Prix Gold badminton championship after he got the better of compatriot Ajay Jayaram in an all-India last-four clash in Basel on Saturday.
The World No 11 Srikanth will take on China's Lu Guang Zu in the next round.
Sindhu pulls out of Uber Cup
P V Sindhu beat world No.12 Busanan 21-17, 21-13 in the women's singles opener, while Kidambi Srikanth demolished Sitthikom Thammasin 21-11, 21-11 in 37 minutes in the men's singles.
Summary of sports events and persons who made news on Wednesday
Indonesian coach Agus Dwi Santoso has been roped in to guide the singles players -- both men and women -- ahead of Tokyo Olympics. Badminton Association of India (BAI) secretary, Ajay Singhania said the visa process has started and Santoso is likely to join the Indian team in the mid of next month.
Earlier, the women's doubles pair of Ashwini Ponnappa and N Sikki Reddy suffered their second successive loss in the event, going down fighting 19-21, 20-22 to Bulgaria's Gabriela Stoeva and Stefani Stoeva to bow out of contention.
P V Sindhu made a positive start to her campaign in women's singles but Kidambi Srikanth suffered a straight game loss on the opening day of the $ 1 million Dubai Super Series Final, in Dubai on Wednesday.
Fifth seed Sindhu will now look to avenge her All England loss against Korea's Sung Ji Hyun, whom she faces next, while Srikanth will meet Thailand's Khosit Phetpradab on Thursday.
P V Sindhu and K Srikanth have been given the top billing in the respective women's and men's singles badminton competitions of the Commonwealth Games
Indian shuttlers had a mixed day in the opening round of the China Open with Saina Nehwal and PV Sindhu easing into Round II, while Kidambi Srikanth and Ajay Jayaram making early exits.
Thomas Cup final: India vs Indonesia
India's leading shuttlers Saina Nehwal and Kidambi Srikanth advanced to the second round of the French Open with straight-game wins, but it was curtains for Sameer Verma at the US $750,000 BWF event, in Paris, on Wednesday.
Prannoy reached the World Championships on previous two occassions.
Srikanth was to play against Momota in the first round on Wednesday but the Japanese world number one pulled out of the tournament on Tuesday
Double Olympic medallist P V Sindhu stayed on course for an elusive gold medal, while Laskhya Sen entered his maiden final at the Commonwealth Games in Birmingham on Sunday.
The Indian men's team is searching for its maiden medal at the tournament. No Indian men's team has ever reached the semi-finals of the Thomas Cup.
Olympic medallist PV Sindhu and Kidambi Srikanth crashed out in the quarter-finals of the French Open after suffering straight-game defeats in their respective matches as India's campaign ended in the singles events.
The star Indian pair of Chirag Shetty and Satwiksairaj Rankireddy will be the key attraction in the men's doubles category. However, they are set to face a stiff competition as the line-up includes the three-time world champion and world No. 2 Indonesian duo of Mohammad Ahsan and Hendra Setiawan alongside another Indonesian pair of Fajar Alfian and Muhammad Rian Ardianto, who are currently ranked eighth in the world.
Swiss Open champion Satwiksairaj Rankireddy and Chirag Shetty strengthened their world number six position, while women's doubles pairing of Treesa Jolly and Gayatri Gopichand was static at the 18th position.
For the first time in the history of badminton, two Indians will clash in a Super Series final with Kidambi Srikanth taking on B Sai Praneeth at the Singapore Open, in Singapore, on Sunday.
Srikanth blew two game points in the second game to lose 7-21, 20-22 to Axelsen in the men's singles summit clash.