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Monday, October 27, 2008
Scouting Jeremy Affeldt
Dave Cameron highlights a non-closer reliever. According to the Josh Kalk player cards, in 2007 his fastball speed was 94.4, and in 2008 it was 95.4. A one MPH change is fairly substantial, probably a 0.25 ERA difference. His fastball also moves a bit more horizontally, and less vertically. His curveball also increased by over 1mph, and moves completely differently. Also, his HR/FB numbers are all over the place: career low with Rockies in 2007, career high with Reds in 2008.
The question on the table is always how persistent these changes are. That is, of the guys who have improved their K/BB number substantially, if you split them up between “change in Fastball, curves”, “no change in fastball curves”, is the “change” group more likely to continue to be better than the “no change” group?
In order for PITCHf/x to have value to a front office, they need to know these answers.