Machine Gun Mollies’ pivot (red) and Blitzkrieg Betties’ pivot (green) pass the group on the left to make a path for the jammer at the gymnasium here Sept. 24. The pivot player is identified by a stripe down the center of her helmet and the jammer, who earns a point per lap, has a star on the side of her helmet. The Devil Dog Derby Dames roller derby league, which is made up of status of forces agreement personnel and service members, contended against each other to keep their competitive edge.