Virat Kohli would be a key Indian player for the final match. He was the one who made 84 in the semi final match against Australia and also he made a 100 runs in a match too in this tournament. I think if he doesn't score, it would have to be Shubman Gill or Rohit Sharma who needs to make a big 100 in this match. If one of the top three batsmen couldn't bat long, it will be very difficult for the Indian team to survive in this match.
Generally, every batsman in the Indian team has the ability to score big runs and anyone can play a match-winning innings. If it comes to a big match like the final, then the match depends on the performance of their top order. If their top order fails, they may lose the match in the final. The opponent New Zealand will definitely want to exploit this weakness of theirs. They will definitely try to get Rohit Sharma, Shubman Gill and Virat Kohli back to the pavilion very quickly. If they delay in doing so, then bad news may be waiting for New Zealand.