India's Cheteshwar Pujara said on Saturday that the pink ball and the lights played a role in four Bangladesh batsmen being hit on the helmet during the first day-night Test in for both teams.
Ishant Sharma led an inspired Indian pace attack that left Bangladesh reeling at 152 for six, needing another 89 runs to avoid an innings defeat at Kolkata's Eden Gardens.
Bangladesh lost Liton Das and Nayeem Hasan on Friday to possible concussion. On Saturday, Mushfiqur Rahim and Mohammad Mithun survived hits.
Mushfiqur survived a blow to his helmet by an Umesh Yadav bouncer but managed to stay unbeaten on 59 and take the five-day game to day three.
Mithun was hit by Yadav but batted on only to fall for six to the same bowler.
"I thought the light and the pink ball had a role to play because as a batsman, it is not easy to pick the ball, especially the short balls," Pujara, who earlier made 55 in India's first innings of 347 for nine declared, told reporters.
"As far as I know, they haven't even played any first-class game with the pink ball. So it's not easy."
Mehidy Hasan and Taijul Islam took the places of Liton and Nayeem who were both hit on the helmet by Mohammed Shami on day one.
Pujara batted under lights in the final session of the opening day, putting on 94 runs with skipper Virat Kohli who made a dominant 136.
"Batting under lights was difficult when I batted yesterday. I think the first session is easier to bat because there are no lights," said Pujara.
"When there are lights, the ball starts swinging a little more. So it is a bit challenging."
Pujara also said that India's spinners made the SG pink ball turn more than the Australian Kookaburra which was used in a few Indian domestic matches.