Williamson was asked about his health, and whether he was fit to play.
"It's getting better each day and I certainly feel healthy now. I suppose it just the aftermath of a virus at this stage, and getting the energy levels back up.
"I'm certainly very hopeful of playing tomorrow."
Heavy rain has fallen in the last three days and humidity levels have dropped compared to Kolkata. Some acclimatisation advantages should swing back in the visitors' favour.
Visible cracks means a turning pitch also looks likely. That could see Ish Sodhi, who spent a good stint in the nets working on his variations, considered ahead of Matt Henry or Neil Wagner.
Such a decision would seem harsh on Henry, who was the stand out performer with six for 105 in Kolkata. Wagner's tenacity, particularly as the ball gets old, would also be missed if three spinners are preferred.
Williamson, coach Mike Hesson and senior pro Ross Taylor consulted next to the pitch for several minutes at training.
The captain smothered selection speculation with a verbal forward defence.
"It's tough to say. Looking at the pitch yesterday it was quite bare at both ends. In saying that, there was a lot of weather around and it was a bit soft, so we want to have another look. We are yet to decide on the balance we'll go with."
Three of New Zealand's top seven - Taylor, Martin Guptill and B-J Watling - have averaged under 20 this series. Williamson acknowledged the onus goes on the top order to deliver a first innings in excess of 300, and preferably 350, if they can win the toss and bat.
"Certainly in the last two games if we could have pushed up our first innings total it would have helped a huge amount.
"They are senior players and you certainly back them to put out the performances. It's not easy but they are working hard.
"There have been good performances from the likes of Tom Latham [average 33.75 including two half centuries], a young guy who hasn't spent much time playing in this part of the world."
Williamson said the performances of both batting line-ups were being defined by the conditions.
"You are presented with surfaces that perhaps don't require those 550-run first innings scores where batsmen look pretty. It is sometimes a matter of doing it tough.
"At the moment that 300 mark seems to be a pretty effective first innings total. It hasn't been [a series] where batters have shot 100s. Batsmen making 80 or above have made a significant contribution."
For India, Bhuvneshwar Kumar is out with a back strain, meaning either Umesh Yadav will return or Shardul Thakur will debut.
Indian captain Virat Kohli confirmed opener Gautam Gambhir will replace Shikhar Dhawan to play his first test in more than two years.