Ian Kennedy has one of the better spin rates in baseball on his 4-seam fastball. Before his start against the St. Louis Cardinals last night, Kennedy’s 4-seam fastball was spinning at a rate of 2,411 RPMs. That’s good for 5th among 34 pitchers who have thrown at least 400 4-seam fastballs in the MLB this season. In case you’re unfamiliar, here’s what a 4-seam fastball grip looks like:
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The idea of a 4-seam fastball is to put as little resistance as possible on the pitch. 4-seam fastballs are typically a pitcher’s fastest pitch, and also his straightest.