Abstract: Baseball batting practice apparatus includes a shaft for detachable connection to a vertical wall and a pair of rotatable gear elements mounted thereon. One of the gear elements is an internal gear and the other gear element is an external gear having a lesser number of teeth and eccentrically mounted so as to mesh with the internal gear in one diametral region. A spring is carried by the shaft and urges the external gear into engagement with the internal gear. A ball is suspended from a hub section which is integral with the internal gear. Striking of the ball causes it to rotate on the hub and effects relative rotation between the gears. Indicia on both of the gears indicates the degree of relative rotation and correlates with the impact force on the batted ball.