Justin Nicolino and the defense-independent problem

Justin Nicolino did not have a great start in his last outing, walking five batters with only one strikeout and gave up four runs in just 4 2/3 innings pitched in his start for the Miami Marlins. While control generally was not an issue with Nicolino in 2015, it shows how fragile his game can be. Without strikeouts, something that he is aware he needs, it is hard to make a living in the majors. You have to do a number of other things well.

What kinds of things are talking about? We can talk about the various things that make pitchers better at their job, but essentially the problem is that without strikeouts, Nicolino or other pitchers like him forfeit one of the guaranteed ways to get outs. A strikeout is always an out, and it is mostly dependent on the pitcher and the hitter (with shout-outs to the umpire, weather, and other static factors within a single baseball game). Introduce a ball in play, and there is more uncertainty. Strikeouts might be "boring" and "fascist," but "democratic" ground balls are not guarantees to turn into outs.

There is a difference between hitters and pitchers. Pitchers pitch in front of more uniform defenses, since they more or less work with the same team throughout a given season. As a result, pitchers are more likely to benefit from consistent defensive play from their own defenders than hitters, who face a more diverse set of defenders over any given period of time. That is essentially the basis of the theory behind defense-independent pitching, a truly groundbreaking discovery by researcher Voros McCracken in the late 1990's and early 2000's that shapes the way we evaluate pitchers today. We now know more data about pitchers than ever before, but we have yet to find just how to best untangle defensive contributions from pitching statistics.

The only thing we truly know is that defense plays a difficult-to-see role in how a pitcher performs on balls in play, and they exhibit less control over the results of those balls than we previously thought. Rob Arthur of FiveThirtyEight did some research with StatCast data that indicated that pitchers control about one-sixth of the exit velocity of a ball, with the rest being based on the hitter. That means pitchers probably have some control, but not a lot.

We know that scoring runs involves getting baserunners and moving them over, primarily with power hits. Fantasy baseball fans may be familiar with looking at a pitcher's WHIP, or walks and hits per inning, as an indicator of performance. That is essentially (though not exactly) a measure of baserunners per inning. But what constitutes those things? The "walks" part of it is well controlled under a pitcher's skill level; a pitcher's walk rate "stabilizes" or becomes about 50 percent predictive of talent in about 300 plate appearances, or half a season.

What about the hits part? Well, likely one of the biggest factors in avoiding hits is avoiding balls in play, which means a larger number of strikeouts, walks, hit-batsmen, or otherwise. After all, none of those events can turn into hits, thus you are "preventing" hits by getting strikeouts or other defense-independent events. Once a ball comes into play, it at least has the possibility of becoming a hit.

This is why strikeouts are so valuable. The strikeout is the only form of an out that does not depend on any other factor. Once a pitcher allows a batted ball, he has control over the angle at which it launches and some control over how hard it is hit, but those factors are just a part of whether that turns into an out or a single or a double. Depending on "soft contact" to get outs is a ticking time bomb; eventually, your defense or your luck runs out.

I looked at starting pitchers who had their first through seventh seasons occur from 1993 to 2015, encompassing 105 pitchers who were good enough to last seven seasons in professional baseball. This already provides a survivor bias of the "best of the best," guys who were talented enough to get to that point who are automatically better than the many who wash out. Out of those 105 pitchers, only 34 posted a BABIP lower than .290 over their first seven seasons, about a solid one-third. And this is among the survivors; imagine how much smaller it would be if we included guys who lasted a shorter time period or even Triple-A / Quad-A types into this group.

Is it possible to figure out which pitchers are going to be those guys? Not particularly, especially in a player's career. It makes it far less likely that Nicolino will be able to maintain a below-average BABIP to fuel his success. Like he himself said:

"I’d like to know the answer myself. Maybe it’s a matter of making some minor adjustments, and that will come with getting older. I realize I can’t always rely entirely on weak contact to get outs. I need to figure out how to miss more barrels."

Perhaps refining a third pitch in addition to his fastball and change-up is a start, particularly with a curveball in mind. Maybe it is tuning up his location of these individual pitches with his supposedly strong command. Either way, he has to miss more a lot more bats to succeed.