Fastball Velocity and BABIP

On MLB Network's "Top 10 Right Now" series, Brian Kenny and company ranked reigning AL Cy Young and MVP Award winner Justin Verlander second among starting pitchers. The discussion soon turned to Verlander's batting average on balls in play, which was just .236 in 2011.

While noting that many different factors can influence a pitcher's BABIP -- batted ball profile, defensive quality and park dimensions being just a few -- Kenny posited that Verlander's BABIP might not regress to the mean as much as other pitchers because of his elite-level velocity. Verlander's heat, which averaged a MLB-best 97.4 mph last year, might allow him to induce weaker contact (when hitters do make contact) and thus result in a lower-than-average BABIP.

Does that theory ring true? To get a rough idea, I placed all fastballs thrown in the majors into four bins based on fastball velocity: those tossed under 90 MPH, 90-92 mph, 93-95 mph and finally 96+ mph. The Verlander-level fastballs did have a slightly lower BABIP than the lower-velocity fastballs from 2008-2010, but the difference was minimal:

Velocity	08 BABIP	09 BABIP	10 BABIP
96+ mph	0.303	0.307	0.301
93-95 mph	0.304	0.302	0.311
90-92 mph	0.305	0.312	0.302
> 90 mph	0.307	0.308	0.305

Something seemed to change in 2011, however. Those popping the mitt at 96 mph or higher had a far lower BABIP:

Velocity	11 BABIP
96+ mph	0.283
93-95 mph	0.303
90-92 mph	0.3
> 90 mph	0.301

While the spread in BABIP among higher and lower-velocity fastballs was just a few points from 2008-2010, there was a nearly a 20-point gap in 2011. Check out the in-play average by pitch location for 96+ mph fastballs from 2008-2010, compared to 2011.

In-play average by pitch location for 96+ mph fastballs, 2008-2010

In-play average by pitch location for 96+ mph fastballs, 2011

BABIP fell a little on 96+ mph fastballs thrown up in the zone, but the biggest dip by far came on pitches thrown in the middle third of the strike zone vertically. Middle-zone fastball BABIP fell by over 30 points:

Part of Zone	2008-10	2011
Up	0.262	0.257
Middle	0.323	0.291
Down	0.32	0.309

Verlander himself was a big beneficiary of the high-velocity fastball BABIP decline: his fastball had a .231 BABIP in 2011, third-lowest among qualified starters. Despite his zip, he actually had a .315 BABIP with his fastball the previous three seasons.

So, what does this all mean? If I knew, I'd be high-tailing it for Vegas. What we do know is that in a sample of over 2,800 balls put in play in 2011, hitters had an awfully hard time making forceful contact and getting hits on fastballs with Verlander-like velocity. There seems to be something to the "more velocity equals lower BABIP" theory. But figuring out whether the huge split that we saw in 2011 will persist is, well, about as easy as trying to hit a Verlander fastball.