September is an unusual time to play cricket in Kolkata. The monsoon is only just winding down and grand Puja festivities are around the corner. Eden Gardens has never hosted a Test in this month. Add the freshly relaid square and the overcast, muggy weather to the mix and there is an uncertainty about what to expect from the conditions.

There is less doubt about India's combination for the second Test against New Zealand, but they have added offspinner Jayant Yadav to the squad just in case.

Jayant's inclusion as a replacement for the ill Ishant Sharma might seem odd, but it makes sense given the occasional discomfort R Ashwin bowled with in the first Test in Kanpur. Ashwin said he had gone into the match without having bowled a lot in the previous 25 days because of a corn, a painful area of thickened skin, on the middle finger of his bowling hand.

"This game especially, I have a corn on my finger and I haven't bowled a lot in the last 25 days," Ashwin had said after the third day in Kanpur. "I'm not very happy with the way it has come out so far. I just hope that I can do better in the series."

Jayant is likely to be on stand-by if the corn proves too painful for Ashwin to play in Kolkata, but India's coach Anil Kumble said all 15 players were available for selection. Even if Jayant doesn't play, bowling alongside Test spinners to Test batsmen in the nets is valuable experience. Ashwin did not bowl at practice two days before the Test, but that is no indication of his fitness because others had also opted out of the optional training session.

Among those who turned up, Virat Kohli practised batting against a rubber ball, presumably to get used to a bit of spongy or uneven bounce. He had failed to control a slog sweep in the second innings in Kanpur, top-edging for a catch.

Shikhar Dhawan had a long net, which is indication that he will open in KL Rahul's absence though Gautam Gambhir was brought into the squad. That much was clear because as soon as the first Test finished in Kanpur, batting coach Sanjay Bangar and Kumble arranged a practice session for Dhawan on the fifth-day pitch at Green Park.

Kumble, though, welcomed Gambhir back into the squad. "I think it's really nice to have Gautam back," Kumble said in Kolkata. "Unfortunately Rahul got injured in the last Test match. I think for some reason something has been happening with the openers. Vijay got injured in West Indies. Now Rahul. It's unfortunate because Rahul was batting brilliantly. Having said that, Gautam has done really well in domestic cricket. He's part of the 15. I don't want to give away anything with regard to team combinations."

Rohit Sharma, whose place in the side is always debated, might have earned breathing space with a half-century in the second innings in Kanpur, but Kumble has not forgotten the shot he played in the first innings to throw away a start of 35.

"Generally over the last one year, we have constantly gone with five bowlers but in the last Test match we felt that four bowlers and the additional batsman was important, and that's why Rohit came into the team at No. 6," Kumble said. "Him batting well certainly augurs well for us. In the first innings, obviously he was disappointed with the way he got out. That's something which he is aware of and when he played in the second innings, it was a brilliant innings.

"That knock, with Jadeja in that partnership of 100-plus, was crucial as well for us to take the game away from the New Zealanders and ensure that we dominate that session. That momentum got carried over when we went on to bowl as well. So in that sense, Rohit contributing was a huge boost for not just the team, but I'm sure it would have done a lot of good for his confidence."

Whether India play five bowlers or four, and how comfortable Ashwin feels, will only be known during and after their final training session before the Test. The conditions on the eve of the match will also play an important role, though Kumble said he wasn't worried about them.

"I still haven't had a look at the pitch," he said. "Yes it's early in the season, there's been a lot of rain in the air and I hope rain doesn't play spoilsport during the Test match. It will be a good wicket. I've spoken about this before the start of the series too - that whatever wicket is there, we have the squad to encounter any challenge and adapt to any conditions. So we're not really worried too much about the pitch and what it can do, what it cannot do. We have all bases covered."

Sidharth Monga is an assistant editor at ESPNcricinfo