Kapur was the only one under par at two-under with one more hole to play while Lahiri and Jeev Milkha Singh shot even par 72 and the fourth Indian in the field, SSP Chawrasia had also a bumpy back nine as he ended at one-over 73.
Kapur was tied 12th with one more hole to play, while Lahiri and Jeev were tied 30th and Chawrasia was tied 61st.
Sweden's Robert Karlsson (67) had two birdies in last three holes to take sole lead at five-under while evergreen Miguel Angel Jimenez, Jorge Campillo, Chris Wood and Korea's Y.E.Yang were tied second with rounds of four-under 68 each.
India's top ranked star, Lahiri closed with a hat-trick of birdies, while Kapur fought his way back from a disastrous triple bogey on the back nine. After being two-under through 12, Kapur's triple on 13th was a big setback. But the 32-year-old, still looking for his maiden European Tour title birdied the 14th, 16th and 17th for a brilliant fight back.
"The finish will give me a lot of confidence going into the second round. I hit the ball pretty good, but need to get other parts of the game working better," said Lahiri.