Abstract: A slidable card device is disclosed for assisting coaches, and assistant coaches, in alternating player positions during a T-Ball League or Little League ball game. In the preferred embodiment, the invention includes a thin, generally rectangular housing or sheath having a front, a back, two closed sides, and two opened ends. The front of the sheath includes a roster box for the coach to handwrite the names of his/her players in column format, as the players show up. Next to the player names is a viewing window which exposes an insert card inside the sheath. This insert card has a series of preprinted matrices that match the number of possible player positions for a ball game. Once the number of players has been determined, the coach selects which matrix appears in the window. Each matrix includes a series of columns which lists the possible player positions, for that game, in various orders.