Do you know the real secret to having a winning Roller Derby team? Nope, not skating skills. Nope, not 50 pull-ups a day. Nope, not all the best transfers from around the world. It’s refs and NSOs. Dedicated refs at your training sessions and NSOs at your scrimmage sessions. "The best derby is precise, disciplined, skilled, legal derby. And you only get that with the help of the zebras in the middle."