There's pressure on the catcher to call the right pitch. There's pressure on the coaches and manager of having their players in a position to succeed.
It can make or break your reputation. If you can do it, they'll talk about you in awe long after you've left. If you can't you'll always have that proverbial asterisk next to your name.
So, why can some guys make clutch situations look like batting practice, while others choke time and time again?
The secret? It's all upstairs, my friend. The higher you advance in baseball, the more true this becomes.