(Originally published at The Flagrant Fan)
In a post yesterday, I pondered relief pitchers like Chad Qualls, Matt Albers and Jake McGee who have unexpectedly increased their fastball velocity with age. Their careers piqued my curiosity. And so I took a look at pitchers who have pitched in relief since 2010 and if their velocity has regressed or not. Let me share what I have discovered.
First, let me disclaim a few things. As always the disclaimer that I am not a math guy with a great handle on how to figure these things out. I am more like Joe Posnanski in knowing enough to be dangerous but not nearly as good at him at writing about my feeble discoveries and calculations.
Secondly, I am using Fangraphs.com’s Pitch Type tool which lumps all fastball types together (4-seam, 2-seam, sinker). While that is inconvenient, it does make it easier than tracking three different pitch types.
And lastly, I am not talking about success rates, movement, the value of the fastball or anything but velocity.…