In a field that has no less than 17 Indians, Rahil Gangjee, Chiragh Kumar and Abhijit Chadha shot four-under 67 each to be tied eighth, while Gaganjeet Bhullar, Kapil Kumar and Jyoti Randhawa carded two-under 69 each to be tied 25th.
Rashid Khan and SSP Chawrasia scored one-under 70 each to be tied 37th as did Daniel Chopra. Himmat Rai scored even par 71 to be tied 73rd.
Thitiphun was off to a seven-under 64 start in the first round lead. The 23-year-old Thitiphun, who is seeking a first win on the Asian Tour, stormed home in 29 and his round included eight birdies. Thitiphun needed only 21 putts during the round.
Young Korean Jeunghun Wang and Bangladeshi Siddikur Rahman shot 65s to trail by one while Lahiri and 2013 champion Scott Hend of Australia were amongst those bunched on 66.
"It's back to the usual I guess," said the current Asian Tour Order of Merit leader. "I think it was a solid round of golf. I misread a few. Hopefully I can make those six or eight footers through the rest of the week."
Lahiri said, "Honestly, I can't complain. Hit a good putt on six, seven, nine, 11 and 12. Very good putt on 15 but that didn't drop. If I had dropped two or three of those, I won't have felt too terrible. I'm not feeling bad. I'm happy with how I hit it. Hopefully I can make those six or eight footers through the rest of the week.
