Wow! That was a real nailbiting finish to the first test. Well done to the New Zealand bowlers to hold their nerve as India's batsmen got close. There was some great bowling, and also some great batting at times. Maybe the difference between the teams was that New Zealand in that final innings made fewer tactical blunders.
I'm sure every armchair pundit has their own opinion of where the match was won and lost, but one that stands out for me is Virat Kohli's lapse of concentration against Neil Wagner. Aggressive batting is great to watch, but it has to give way to common sense if you want to stay at the crease. Trying a pull shot at a ball that isn't terribly high and w-i-d-e outside off stump would be a suspect choice of shot even in a Twenty20 game, bad in any Test match, and downright appaling in a test that was as closely balanced as this one. What did he expect to happen?
Anyone who has ever faced fast bowling will know that there are some basic laws of physics going on. What's of great importance in determining where the ball will end up after hitting your bat is the relative motion of the ball with respect to the bat, and the angle of incidence of the ball on the bat. The ball doesn't go in the direction that you hit it. Since it's carrying momentum (and a fair bit of it), what you do when you apply a force with the bat is that you change the ball's momentum. It's the change in momentum, not the final momentum itself, that's equal to the impulse (force times time) that you give to the ball. These things are vector quantities, that is, they have directions. If you don't hit the ball in the exact opposite direction to where it is coming from, the final momentum of the ball won't be in the direction in which you hit it (apply a force on it).
To pull a cricket ball through midwicket means that your bat's got to be pointing somewhere towards mid-on when you make contact with it. Try doing that when you're stretching out for a ball that's w-i-d-e outside off stump and you'll get the idea of why this shot was never going to work. Guiding it to the point boundary would have been a whole lot safer and effective, but then I'm sure Mr Kohli is well aware of that now.