How do you throw a slurveball?

To throw a slurveball, do everything exactly like you would when attempting to throw a curveball (including your grip), BUT rotate counterclockwise (clockwise for lefties) at release; it's very subtle. This action, along with the pressure of your ring and middle fingers, are the two keys: rotation of hand on release and grip.

Your ring finger would rest to the left of this "raised seam" or "suture/baseball laces." Rotate just the ring and middle fingers slightly outward as your arm comes through -- and that should create the tight spin for both movement down through the strike zone plus "cutting action" like a traditional slider away as it approaches -- a slurve.

To get the downward movement (similar to a curveball), throw the slurve using a standard curveball "wrist snap" at release of this pitch.