As you may expect, people around baseball were talking Freddy Peralta yesterday. For example, Jeff Sullivan over at FanGraphs posted an excellent article on the Brewers’ newest sensation. I strongly recommend you give that article a look, because it inspired me to analyze Peralta’s delivery further. Sullivan’s piece covers Peralta’s deception, but also touched on something I found particularly interesting: Peralta nearly topped the league in “perceived velocity difference” in his start on Sunday.
Perceived or effective velocity difference refers to a pitcher’s release point, and how it either adds or subtracts velocity from the perspective of the batter.