Moe -- The first thing we have to do is be sure we're all talking about the same spot on your thumb. Picture a circle (representing a ball) with the thumb hole near the bottom and the fingers toward the top. Now picture your thumb being inserted into the thumb hole. Where on the hole does the callous hit -- top of the hole is 12:00, right side is 3:00, bottom is 6:00, etc. The problem may be caused by improper pitch, but it could also be caused by improper gripping (bending the thumb at the knuckle, or "knuckling"). -- JohnP