Abstract: An apparatus is provided to aid training users to throw a ball with proper biomechanical form. The sleeve is open on one end to receive a weight, ball, and user's hand. The sleeve is closed on an opposite end to maintain the weight within the sleeve during use. A wrist portion may be attached to the open end of the sleeve and is releaseably securable around the user's wrist, so as to removably secure the user's hand, holding the ball, within the sleeve. In practice, a user wearing the sleeve may perform each motion associated with throwing a ball, including releasing the ball within a passageway defined by the interior surface and closed end of the sleeve. The aforementioned weight acts as a lead or guide, directing the user's body through all physical motion experienced over the course of a properly executed pitch.