SPECULATOR: In-season pitch changes, 2019

As we all know, in-season pitcher performance comes with peaks and valleys. Sometimes we can chalk it up to simple variance—a hot or cold stretch where command comes or goes, balls find holes at the wrong time, etc. Other times, a tangible change in a pitcher's pitch mix, release point, or velocity might be driving those new levels of performance. It's those "other times" that draw our speculative eye.

The advancement of pitch-level data allows us to track such things, so we'll look at eight pitchers who've switched things up this season to the benefit of their skills and/or results. All pitch graphs are courtesy of BrooksBaseball.net, with statistics through July 28.

American League 

Lucas Giolito (RHP, CHW)

We can see a big change in...

Almost!

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