The ornamental design for a ballpitchingtrainingdevice, as shown and described.
FIG. 1 is a perspective view of the ball pitching training device showing my new design.
FIG. 2 is a rear elevational view thereof.
FIG. 3 is a front elevational view thereof.
FIG. 4 is a top plan view thereof.
FIG. 5 is a bottom plan view thereof; and,
FIG. 6 is a left side elevational view thereof, the right side view being a mirror image of the left side view.
The appearance within the unshaded region in FIGS. 1, 2 and 4, including the structure represented by the broken lines therein forms no part of the claimed design.