Kapur, playing for the second year running at the US Open, carded a two-over 72 after being three-over after just six holes. He was tied 52nd. Overall he had three birdies between ninth and 16th against five bogeys.
Lahiri had a tougher day with a five-over 75 that put him in a grave danger of missing the cut at 123rd place. Lahiri dropped a double bogey, five other bogeys and had just two birdies in his 75.
After two pars, Kapur three-putted from 40 feet on the par-3 third for his first bogey. He made further bogeys on fifth and sixth. But he staged a great fight back from there to pick birdies on ninth with a lovely tee shot on the par-3 and holed from seven feet.
Another birdie came on 12th and then came two more disappointing bogeys on 14th and 15th. A bogey on 14th was followed by a visit to greenside bunker on 15th and that was another bogey. A minor consolation was a 30-foot birdie on 17th.
Lahiri had birdies on 12th and 17th against one double and five bogeys.