What I’m about to tell you is perhaps the most annoying thing to hit the baseball world since Nomar Garciaparra’s incessant batting-glove re-strapping. MLB has moved on from PitchFX and now records data exclusively using Statcast’s Trackman systen. The PitchFX era is dead.
This is problematic because we cannot compare 2017 to previous seasons with any real validity since FanGraphs and Brooks Baseball pull data from MLB. It’s is a huge issue. The change effectively renders 10 seasons worth of pitch data more impotent than the target market for all the pills being hawked during baseball broadcasts.
PitchFX and Trackman technology dramatically differ. The former typically measures velocity from 50 feet, while the latter measures it immediately when the ball leaves pitchers’ fingertips. As a result, there has been a spike in velocity of nearly one mile per hour across all pitches in the young 2017 season. Even pitch movement might be affected, convoluting analysis that seeks to identify the game’s best pitche(r)s.
The annoyance is perfectly illustrated by Jon Lester’s new data. For example, Lester averaged 93 MPH last year, but averaged only 91 MPH during his Opening Night start. If PitchFX were still in use, Lester’s velocity might actually have read around 90 MPH. A three-MPH drop in velocity is slightly disconcerting enough to deserve further inquiry, but that’s for another time.
I imagine people will be attempting to adjust PitchFX ratings using a Trackman scale, but we’re kind of in the woods until such a scale is produced.