Abstract: A baseball batting trainer utilizing an elongated guiding rail, one end of which defines a positioner for the rear foot of a batter, there being a moving foot guide which slides along the rail while controlling the straddling movement of the front foot, and which hits a stop positioned on the rail at a certain point to define the furthermost position that the batter's front foot should assume before the swing. A rear stop behind the front foot guide defines the position of the front foot before the straddling movement starts, these stops being adjustable to accommodate the styles of different batters.