For the most part, the vulcan changeup is a variation of the circle changeup, but instead of the thumb and index finger making a "circle," those fingers rest on the side of the baseball, as pictured above.
The vulcan changeup is gripped deep in the hand.
Place the baseball between your middle and ring fingers (instead of the index and middle fingers, as with a circle changeup). Throw the pitch with fastball arm speed but pronate your hand by turning your thumb down, to get good downward movement on it.
The key is to make sure the "V" shape of the fingers are pointing toward the catcher when the pitch is released.
It's also important to follow-through just like you were throwing a fastball.
How do you throw your pitches? Post pictures of your pitching grips on my baseball pitching discussion forums.
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