Many readers commented that what I noticed might just be a change in the MLBAM classification algorithm, rather than in Zito’s repertoire.
I’m not surprised, since I had the same concern myself.
What follows won’t end the matter and maybe I’ll get on this again in a few weeks.
Here are the speed/movement charts of Zito’s 2008 hard curve and his (alleged?) 2009 slider.
I see quite a good separation in all of the graphs, that makes me feel like they are two different pitches, whether they are a slider and a hard curve or something with different names.
Speaking of names, here’s what his catcher Bengie Molina said after a gem pitched on July 7 (I happened to be at the park that night): “He did a great job. The curve ball was working, the slider, the changeup—everything was working”.
It seems that a slider is indeed in Barry’s quiver, and if Bengie says it was working, he might have called for it a few times.
MLBAM algorithm sees a slider among Zito’s pitches; BIS video scouts see a slider too (they were also seeing one before 2008, but they are seeing it twice as much this year); Bengie Molina talks about a slider; for the time being I’m going to stick with the new pitch hypothesis.
I’m currently watching some videos of this year and 2008; I hope to give you an update.