The two players fought tooth and nail till 22 points before the Indian faltered to hand the first game to his opponent.
Rajawat will take on eighth seed Kunlavut Vitidsarn of Thailand next.
Two-time Olympic medallist Sindhu will next play Japan's Natsuki Nidaira, while Sen will be up against Ygor Coelho of Brazil.
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.
The CM expressed hope that budding athletes and sportspersons in the state can take inspiration from his achievement and adopt the same attitude of hard work and dedication shown by the Indian shuttler.
Lakshya Sen lost a tough three-game men's singles semifinal against Thailand's second seed Kunlavut Vitidsarn at the Thailand Open in Bangkok.
P V Sindhu, H S Prannoy and Kidambi Srikanth booked their places in the quarter-finals of the Malaysia Masters Super 500 tournament.
Lakshya Sen will take on Kidambi Srikanth in an all-Indian second round clash.
Viktor Axelsen said the young Lakshya Sen would be among the favourites to win a gold medal at the Los Angeles Games in 2028.
Lakshya Sen upset World No 4 Loh Kean Yew of Singapore in the round of 32 match at the Malaysia Masters.
In mixed doubles, Tanisha Crasto and Dhruv Kapila advanced to the second round with a 8-21, 21-19, 21-17 victory over Chinese Taipei's Chen Cheng Kuan and Hsu Yin-Hui.
Satwiksairaj and Ashwini showed top-notch fighting spirit before going down
Kidambi outperforms Sen, Sameer scores upset win
Prannoy signs off with maiden World Championships bronze medal after losing semifinal to Vitidsarn
India's two-time Olympic medallist P V Sindhu romped into the women's singles semi-finals of the Indonesia Masters Super 750 badminton tournament with an easy victory over Turkey's Neslihan Yigit, in Bali, on Friday.
World champion Kunlavut Vitidsarn crashed out of the India Open Super 750 badminton tournament
Disappointed not to get gold but bronze means a lot: Prannoy
World No. 1 Yamaguchi, however, had to toil hard to get across three-time world champion and Rio gold medallist Carolina Marin of Spain 21-17, 14-21, 21-19 in the day's first match at the IG stadium in New Delhi.
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.
Sourabh will next face Korea's Heo Kwang Hee for a place in the men's singles final.
If Sindhu and Saina win their respective second round matches, they will face each other in the quarter-finals.
Sindhu, Sen look to regain lost touch in Canada Open
Lakshya Sen mounted a remarkable comeback to become the first male Indian shuttler to qualify for the singles semi-finals at the Olympic Games.
Returning to action after a break, double Olympic medallist P V Sindhu saw off Turkey's Neslihan Yigit in straight games to join compatriots Kidambi Srikanth and Sameer Verma in the second round of the Denmark Open in Odense on Tuesday.
Denmark's Viktor Axelsen and Japan's Akane Yamaguchi's dominance continued as they stayed on course for a second successive title.
Lakshya Sen continued his rich vein of form as he sent the world No. 1 and top-seed Axelsen packing
The sixth seeded Indian from Uttarakhand, who had won a bronze medal in the last edition of the competition, notched up 21-19, 21-18 upset win over Vitidsarn in the summit clash that clocked 46 minutes.
India's top shuttlers P V Sindhu and Kidambi Srikanth registered straight-game victories to make impressive starts to their singles campaigns at the season-ending BWF World Tour Finals in Bali on Wednesday.
Satwik and Ashwini, who reached the semi-finals at Toyota Thailand Open Super 1000 in January, will meet the winner of the match between fifth-seeded Malaysians Tan Kian Meng and Lai Pei Jing and Germany's Jones Ralfy Jansen and Kilasu Ostermeyer.
Lakshya Sen sails into third round of World Championships
The win ensured Srikanth's dominance over his younger countrymate as he took his head-to-head record to 3-0 over Lakshya.
Indian badminton stalwarts P V Sindhu and Saina Nehwal suffered contrasting fortunes at the Malaysia Open Super 750 tournament, the former progressing to the second round and the latter bowing out after losing her opener in Kuala Lumpur, Malaysia, on Wednesday.
Satwiksairaj Rankireddy and Ashwini Ponnappa notched up an upset win over the World No 8 and second-seeded Indonesian pair of Hafiz Faizal and Gloria Emanuelle Widjaja in the opening round.
India's badminton ace P V Sindhu entered the summit clash of BWF World Tour Finals with a hard fought win over Akane Yamaguchi of Japan in the semi-finals, in Bali, on Saturday.
Sourabh Verma and Ajay Jayram also entered the second round
'Until April 2024, we have the qualification period so until that we might push for more tournaments but the plan is to pick and choose after you qualify and then gradually peaking before the Olympics.'
Summary of sports events and persons who made news on Saturday
Lakshya Sen said the win against reigning All England Champion Li Shi Feng gives him confidence and belief in the Olympic qualification year.
India's HS Prannoy showed nerves of steel, advancing to his third successive quarterfinals at the World Championships.
The top Indian players, including Sindhu, Saina Nehwal and Srikanth have failed to lift the prestigious trophy
