Lahiri, who plays at the Olympic Games in the closing stages of a packed season, had two birdies, three bogeys and a crippling double bogey that saw him tumble down the leaderboard.
Lahiri got off to a terrible start with bogeys on third and fourth as he missed very short par putts inside five feet and that set the trend for the day, even though he stemmed the rot for next five holes.
A birdie on 10th gave him hopes of revival but bogey on 13th and a double on par-4 15th meant he was four-over with three to play. A birdie on 17th was a consolation but it left him with a huge task of making up on second day.
Lahiri had only 50 per cent accuracy off the tee, but he had 16 greens and he missed a lot of putts which meant a disappointing card. Through this season, Lahiri has played well from tee to green and then missed a lot of putts. It has resulted in just one Top-10 finish in the season where he has made 16 cuts in 20 starts.
Lahiri said, "Putting has been the area that I need to work on. I am trying but there is still some work to be done. Hopefully I can get things moving on second day and hopefully on the weekend."
Jimmy Walker, who missed the cut at the Open, began the PGA in style with sole lead at five-under and he is one ahead of Emiliano Grillo and Ross Fisher. Open winner, Henrik Stenson is in Tied fourth with five others including Martin Kaymer at three-under.
Among the other big names, Jordan Spieth and Jason Day shot 68, Danny Willett shot 71 and Rory McIlroy went for 74. The PGA Championships is the last major and includes 97 of the world's Top-100 in the field.
Asian Tour honorary member KJ Choi and Australia's Scott Hend opened their campaigns at the US PGA Championship with matching two-under-par 68s to stay three shots back of American leader Jimmy Walker on Thursday.
Choi and Hend both mixed their cards with four birdies and two bogeys to share ninth place with 10 other players that include world number one Jason Day and Major winner Louis Oosthuizen of South Africa at Baltusrol.
Japan's Yuta Ikeda signed for a 70 to be bunched in 36th place that also includes Thailand's Kiradech Aphibarnrat. Korea's Younghan Song and current Merit leader Marcus Fraser of Australia returned with matching 71s while 2009 PGA Championship winner YE Yang and Thongchai Jaidee are a further shot back after carding identical 72s.
Apart from Lahiri Korea's Jeunghun Wang also had a day to forget with his opening 73.