Where Has All the Velocity Gone?

One day after the anniversary of his second career no-hitter, Jake Arrieta returned to the mound in Cincinnati and helped deliver a series-clinching victory for the Cubs. While the powerful righty surrendered two home runs on a blustery Ohio afternoon, there were signs that the 2015 Cy Young winner was beginning to right himself after an out of sync 2016. Jared Wyllys catalogued some of the changes that Arrieta has made so far in 2017, but there’s more at work that morphing pitch selection.

On Saturday, Arrieta tallied eight strikeouts and walked nary a batter. The zero in the walk column is impressive; the eight in the strikeout column is encouraging. And, importantly, it  looked as though Arrieta finally dialed up his fastball and other pitches to the velocity at which he sat last season—setting me on a writerly path that takes me beyond Jake Arrieta.

The biggest mystery for those of us watching the Cubs early this season, and for many who write about baseball in general, has been the amazing, incredible, stunning disappearing act of the starters’ velocity. (So sue me, I buried the lede). Seeing Arrieta pump his fastball in at around 93 mph against Reds hitters on Saturday might have helped dispel some of the rampant speculation about the missing velocity so far this year. Was the switch from PITCHF/x to Trackman causing some weird missed readings or failing to calibrate correctly? Did Arrieta and Hendricks have “dead arm,” as Joe Maddon might have suggested? Were the softer fastballs early on a strategic ploy to keep the starters’ arms healthy for another late postseason run? And, if so, would that even be a smart plan, considering the uniqueness and weirdness of pitchers’ mechanics and psychologies and health?

For ease of comparison, we’re going to look at the Cubs’ incumbent starters and omit Brett Anderson. Anderson’s injury history and change of ballparks makes season-to-season velocity comparisons difficult, and he’s generally not as useful for the purposes of this analysis. The Cubs’ four other starters have posted the following fastball velocities, from Brooks Baseball:

The first thing that I’ll note is that Brooks has changed many of these marks, as they work to adjust to the Trackman system. This is especially noticeable for those of you who might have perused the data from the opening series in St. Louis, as the now-adjusted numbers are one or two miles-per-hour faster than the initial readings.

The second thing is that there is a stark difference between the velocity readings taken at Wrigley Field and those taken in the three other NL Central parks in which the Cubs have thus far played. All four starters posted their lowest average fastball velocity in Chicago, and in the case of Hendricks, this was particularly worrisome at the time. Hendricks, on Tuesday night in Pittsburgh, got his fastball up to 88 mph—the velocity at which he needs to sit to be successful—which dispels some of the concerns over his 84 mph readings in Chicago. And a handful of the Cubs’ returning relievers—Hector Rondon, Carl Edwards, Jr., and Mike Montgomery—have also seen velocity dips this season, according to Brooks. It’s possible that there are just differences in the way that the velocities are being read, particularly at Wrigley Field, that have caused some phantom velocity dips for these pitchers.

If we’re consuming this data, we now know at least what grains of salt with which we need to season it.

The final two columns, though, are what cause legitimate, non-Trackman-weirdness concern. Once again, there is a one-to-two mile-per-hour drop for all four pitchers in their average fastball velocities. Overall, from 2016 to 2017, the Cubs’ starters have lost significant zip. It’s important not to look simply at holistic, average velocity, though. Since there’s a big difference between Wrigley numbers and away park numbers, we can take a look at their average fastball velocity for away games this year and see if that’s more in line with their recent career marks.

Splicing it this way reveals that it’s not just a Wrigley Field problem. For Lackey and Hendricks, away parks offer a slight boost, but each pitcher is consistently underperforming their 2016 numbers at home and away. It’s important to note, however, that the home/away splits from 2016 for each pitcher offer very small differences, whereas the 2017 splits are between one-half and one mile-per-hour. Time, and possibly recalibration of the systems tracking velocity, will bring those numbers closer together.

But there are many ways to chop up this data that might be more helpful than a simple year-to-year comparison. After all, it’s April, and it’s possible the playoff hangover has lingered for the Cubs’ arms. To test this theory—that these pitchers might be experiencing velocity loss due to a short offseason and big 2016 workload—we can compare their April velocities this season to theirs last year. One last table:

Arrieta is the conspicuous one here. He’s down 2.5 ticks on his fastball (which he admittedly throws much less often than his sinker) compared to last April. For what it’s worth, Arrieta’s sinker numbers are almost identical to his fourseam marks in both months. The other three have seen lower marks, but less drastic ones. This is still somewhat confounding: unless the starters have been instructed to ease up on their heaters this early, then the chances of “dead arm” or real health/endurance issues are quite high.

For Hendricks, the problem might be a real mechanical one. Sahadev Sharma quoted Hendricks ($) as describing his lower body as more in-sync in his Pittsburgh start, where he topped out at 88 mph. Arrieta’s finicky mechanics are now the stuff of legend, and it’s possible that he is out of sync himself, as he was for most of 2016. Lester and Lackey are getting older and they both have quite a bit of mileage on their arms, in addition to their large workloads from last season, so they could just be starting slowly.

Ultimately, there’s little to do but wait and see. We’ll need more than few starts to determine if something is wrong long-term for any of these pitchers. If any have dead arm, or need mechanical tweaks, or are simply getting old, we won’t really know until we have more data. I guess I should I apologize for these tepid non-conclusions: I don’t know where the velocity has gone! Soon enough, we’re going to find out.

Lead photo courtesy Charles LeClaire—USA Today Sports