Your Delivery Should Never Be Individual Pieces Balance. It is the ultimate velocity killer and one of the biggest reasons pitchers develop injuries. I have had the privilege to learn from and study the deliveries of some of the greatest pitchers in the game during my assignments with MLB teams. Mariano Rivera, perhaps the greatest pitcher in our lifetime, has been our pitching model since we filmed and presented our "Calm before the Storm" pitching video with him in 2001. It has become the most watched pitching video on the market. The next time your son's pitching coach does balance drills such as "stop in the middle of your windup" or "pause to catch a ball while pitching and then throw,"