Originally Posted by Mario-Rijo
It's just a curveball? Well yeah and not quite. It basically does the same thing as a straight curve but is a better pitch in theory if you can master it. They generally have better movement (due to a tighter spin) and because of the way you throw it it comes out of the hand looking like a fastball. Watsons kind of plays more like a splitter or filthy change IMO (with the later breaking drop), or at least it did when he was in Dayton. It really is a sick pitch for him but apparently the kid can't get anything else to work right. BUt yeah it's not knuckler like in anyway really, in fact I think they call it a spike curve also.
They do also call it a spike curve. Its all about the grip. You use your index finger on the seam like you would grip a knuckle ball (shown to me by Phil Hughes of the Yankees - Name dropper).
Side note though is that Sean Watson actually stopped throwing the knuckle curve for a while there because he couldn't throw it for strikes at all. Once he left Dayton hitters figured out he couldn't throw it in the zone and they stopped swinging at it. He is throwing a curve again, but I am not sure if its still the knuckle curve or not.