Remember little league? How fun was it to be at the ballpark? All your buddies around, having a good time, playing a child's game. You didn't have a care in the world except maybe post game snacks, ice cream with grandma and grandpa, or what video game you were going to play when you got home. That's what this is supposed to be like. We aren't here to solve the world's' problems, cure disease, or prevent famine. We are here to play a game. So take a deep breath, let loose, and have fun. You've earned the right to be here. This team is good enough to beat anyone here. You've proven it many times this season. Get in there and go down swinging. These coaches have your back, the fans have your back, now focus on doing your job, playing your game, and most of all have each other's back.
I don't really know who the leaders are in the dugout, but I know who the guys are that have been there for a while. I would call the upperclassman over individually and charge them with being the leaders in the dugout and tell them this:
Lift each other up, be vocal, encourage, mentor, but most of all love. It's the love of the game that got you here and it's the love of your teammates that will get you deep into this tournament. If you don't love this game and the guys you're playing it with, then you aren't going to make it very far on talent alone. Every team left is talented. You separate yourselves by working together on every single play. When someone makes a play, good or bad, be the first one there. Keep the vibe alive and believe in your guys. Make them know you have their back no matter what happens.