In Need of Radical Change, D-backs Should Turn to Humidor

Thunderstorms are in the forecast for this weekend’s series in Boston, where the hot, soupy air has had me drenched in as much perspiration as precipitation. Don’t be surprised if we see more than one player wilt over the next few days, and you can bet that most starters will get at least one of the games off. You can’t fight the power of humidity. But can you harness it?

The D-backs have played much of this season without A.J. Pollock and David Peralta, arguably two of the team’s four best position players, but it’s the abysmal pitching results that form the chasm between a playoff version of the 2016 D-backs and the current one, barreling for a 67-95 finish. Every pitching success and failure teaches us more about what it takes to succeed in Chase Field and in the NL West, but there have been oh-so-many failures to learn from, and other than the profile of the incomparable Brad Ziegler, all we’ve really learned about success is that to succeed, you have to be really good and maybe even get tons of swings and misses. Got a great slider with big break? Fantastic. But slip just a little, and a 2013 Patrick Corbin can become the 2016 version of himself even more easily than a Rubby De La Rosa can break through.

Swing-and-miss is a valuable commodity for the D-backs, but it only works for the team because it works for every team. In addition, it’s one of the most consistent pitching profiles. And one of the best. It doesn’t really matter that the gap between swing-and-miss and other kinds of pitching may be greater for the D-backs than it is for other teams; the fact that it’s valued everywhere makes it a poor long term plan for a mid-market club.

That’s nothing new. But consider it in the context of where the D-backs find themselves now. In many ways, the D-backs are still poised to take advantage of the Contention Window they so hastily built around Paul Goldschmidt, particularly with breakout superstar (yes, I’m saying that) Jake Lamb likely in the fold for four more seasons. The pitching staff, however, is in shambles. The D-backs were ready in July to cut some losses with Shelby Miller, and yet not willing to take too scalding a bath to let him go at fire sale prices. Zack Greinke has been really good, but not exactly one of the game’s best, and while Robbie Ray is quickly turning himself into a fairly strong bet, what can the D-backs reasonably expect from De La Rosa next season, if he regains his health? What is Patrick Corbin now? Archie Bradley‘s spring training status next year will likely be similar to that of Ray this last March, and even if Braden Shipley finishes the season with five or eight more strong starts, April failure would pull him from the rotation about as quickly as any of the non-Greinke starters.

Put differently: the D-backs just re-made their pitching staff, a year ago, cashing in essentially all of their budget space and sought-after extra pieces to do so. Can they really do so again this offseason? Can they really do so with better results?

I’m not sure anyone could. I feel like I have a much better understanding of what kinds of pitching translate to the desert than I did three years ago, but other than fitting many of the team’s success stories into three fairly specific categories, all I really can point to is that swing-and-miss profile, and there’s no way to remake the staff that way this offseason. I have no idea how I’d do it, and even if someone could, that’s taking chances on a small handful of specific players, while the rest of the staff treads water, or worse.

So how do you make an entire pitching staff better, all at once, with more or less the same personnel? That’s the challenge the D-backs face this offseason. You could find and install an excellent pitch framer, who could lower the staff ERA by 0.20 or even 0.30 (given what replacement level is for the team right now). You could play around with the fences, maybe, although even the most nuanced version of raising fences might save about six home runs a year. You could find some kind of magical pitching coach, maybe. For most teams, that’s about it. And even if the D-backs were to set their sights on a premier catcher or pitching coach, their chances of landing the right one seem slim to none. Every team wants those.

But there is the humidor possibility; it sure doesn’t seem like the D-backs have one, although MLB does regulate ball storage overall. For most teams, a humidor would actually promote offense; MLB keeps the Coors Field humidor at the 50% humidity mark, the conditions in which Rawlings stores balls. For 27 or 28 teams, that’s a decrease in average humidity, meaning for them, a humidor ball would be ever-so-slightly lighter and just a bit more bouncy than the ones they may currently use. For Arizona, a humidor would be more effective at limiting batted ball distance as the Coors Field humidor is for the Rockies:

According to Dr. Nathan, the difference in humidity between Denver and its humidor accounts for about 2.8 mph in batted ball speed. 0.6 mph of that figure is attributable to the lower weight of a drier baseball; the greater reduction of 2.2 mph comes from the difference in coefficient of restitution (COR). COR is the “bounciness” of a ball; Dr. Nathan uses the word “mushier,” but maybe it’s easiest to think of it as a properly inflated basketball (dry) versus a slightly underfilled basketball (not as dry).

The Denver air averages about 35% humidity, 15 percentage points lower than the 50% humidor; that gap is what the numbers from Dr. Nathan represent. From mid-July through the end of the season, Phoenix air also has about 35% humidity, and we could anticipate a very similar effect. During the rest of the season, particularly in May and June, Phoenix air can be far drier than that, in the 20% humidity range. If Chase Field balls really do live in a 20% humidity environment for much of the year, we’re talking about a difference in batted ball speed of 5 or 6 mph. That may not sound like a lot. But if the D-backs are then yielding that many more batted balls in the high 90s mph and faster, that difference could add up very, very quickly.

Raising fences could trade away some pitching homers for pitching extra base hits, but a humidor does more than that — it’s not just about home runs. With Chase Field’s cavernous dimensions, doubles and triples almost certainly matter more; extra bases tacked on singles and doubles come at a high cost, particularly since the effect of those events can be compounded if they happen more than once in the same inning. Like it or not, Chase Field is a large park with many places for the ball to find open ground. With dryness helping those balls to find ground faster and farther away, great outfielders look amazing, and mediocre ones look horrendous.

Yes, any gains for the pitching staff would most likely be offset by losses for the offense, but this particular offense would probably be fine. They’d hit fewer home runs, but the over-the-fence gap power of Paul Goldschmidt and Jake Lamb still looks good as at-the-fence gap power, slash-and-burn hitters like Jean Segura would still be rewarded by the spacious outfield confines, and “not as good” doesn’t mean “bad.” On the pitching side, it’s just flat out bad.

The D-backs need traction for their pitching staff; they need pitchers like Addison Reed and Shelby Miller and Daniel Hudson to excel the way they might excel in nearly any other park. A tremendous number of pitchers succeed in the majors despite middle-of-the-road batted ball profiles, with ground ball rates in the low 40s. Just not in Arizona. A little bit better goes a long way, particularly when facing opponents who do not play more than three games in a row at Chase most of the time; the toll the park takes on the D-backs staff means exposing the soft underbelly of the bullpen more often for having to play more games in a row at the field on homestands. If the D-backs’ existing pitchers can succeed just a bit more, the pitching staff will succeed more in part because the pitchers will be a bit better, but also because the worst pitchers will pitch that much less.

We need some kind of radical change. Isn’t a humidor worth a try?