New Zealand skipper Kane Williamson missed training on Thursday after being hit by a bug, raising concerns over his fitness for the second Test against India.
Team-mate Tom Latham said the Black Caps were hoping the talismanic batsman would be fully recovered for the first day on Friday as the tourists fight to save the series.
"Kane is a little bit crook (sick) today so he won't be training. Hopefully he'll be fine to go tomorrow," Latham told reporters.
Williamson hits double hundred, New Zealand flatten Pakistan
"There is no discomfort, he is just down with a bug. Nothing too major, he is just resting up and getting right for tomorrow."
New Zealand need a win at Eden Gardens to square the three-match series at 1-1 after they lost the first Test in Kanpur by 197 runs.
Williamson's 124-run second-wicket partnership with Latham in the first innings was a bright spot for the visitors, who had their moments in the game.
Luke Ronchi and Mitchell Santner also hit fighting half-centuries in the second innings and Latham said a little more consistency could reap dividends.
"Nothing really changes too much (from Kanpur). You have to do all the cliche things you need to do at the start of an innings," he said.
"We weren't too far away in the first test. As Hess (coach Mike Hesson) has alluded to, we just need to do things for a little bit longer.
"If we can do that with bat and ball it will a good chance in this match."
