as for me, I think India needs 3 quicks/pacers, esp with likes of Ganguly no longer there to support that dept .... Bhajji, may shine once in a while but as a lone spin specialist, he on many occasions appears inadequate in tests. i couldn't imagine him getting me out when I saw him bowl in the last test
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.... It might not be a bad idea to change spinners in a series. Just like NZ had difficulties with Bhajji in the first test, playing Mishra for the first time could pose challenges for them too
I would recommend Mishra, either in for Bhajji [if the conditions are such that 4 bowlers can run through the side] or Yuvi [if conditions are such that 6 batsmen can do the job and also depending up on Dhoni's availability as he strengthens the batting]
I read abt Dravid being made to keep and bringing in Vijay which is a good suggestion but I don't know if Dravid has it [fitness level] in him to be able to keep and bat in tests. Few years ago that would have been a good option!