On The Frequency of Arbitrary Thresholds

One seemingly trivial baseball event that occurred in the final week of the regular season was an incident involving Mike Minor. Specifically, the manner in which Minor recorded his 200th strikeout came under scrutiny. News cycles galvanized the situation in spite of (or, perhaps inversely, exactly because) neither the Rangers nor the Red Sox were heading to the postseason. 

Put simply, Mike Minor reached 200 strikeouts with some help from a purposefully dropped pop up.

The “incident” was of particular interest given its occurrence at the intersection of a medley of baseball’s arcane guidelines. At it’s center was of course the Rangers enabling their Opening Day starter to pitch longer than he might have without a personal milestone in his immediate future. There was obviously the dropping of an exceedingly catchable baseball. The Red Sox sudden proclivity to engage in first-pitch swinging also should be mentioned. For news outlets, it was a chance to poke at two teams with seemingly nothing better to play for than a singular player’s pursuit of a round number.

200 strikeouts, of course, is an arbitrary threshold. Still, it’s an accomplishment that Minor deemed significant enough to lobby for every reasonable chance to achieve. The Red Sox in turn validated his aspirations through their apparent efforts to quash them. 

The emphasis of this situation seems to be misplaced in my opinion. Not misplaced because Mike Minor shouldn’t be making his every effort to achieve his own goals or because the Red Sox were trying simply to “play the right way”, but because Minor had already reached the more significant milestone hours earlier: 200 innings pitched. 

Like round strikeout totals, innings pitched thresholds are also arbitrary. It is in fact an arbitrary threshold that’s been written about here before. The point here though, is that it’s a threshold that’s trending in the exact opposite direction of the strikeouts milestone Minor was particularly keen to achieve. 

Below is a figure of the number of 200 inning pitchers alongside the number of 200 strikeout pitchers each season dating back to 2000. You’ll see either group has a distinct trajectory.

So, for the past three seasons at least, reaching 200 innings has become a rarer feat than striking out 200 batters. But it’s hard to imagine the Red Sox or any other team taking offense to a player trying to reach 200 innings. The one precedent that comes to mind, Mark Buehrle in his career’s final outing, certainly didn’t draw so much attention as in the case of Minor. Of course, Buehrle attempting to reach an innings threshold doesn’t so directly come at his opponents expense the way a strikeout threshold might. Of additional note is that Buehrle’s appearance came on the eve of a playoff berth for the Blue Jays.

Below is a chart which reflects the data in the figure above.

As shown above, in the early 2000’s it wasn’t uncommon for each team to have three qualifying starters (per the 162+ innings qualification); in the past couple years, more likely each team employs just two. That trend alone highlights the value of pitchers capable of giving their team 200 innings. Meanwhile, two hands used to be capable of counting all pitchers with greater than 200 strikeouts annually. Today that is clearly not the case.

This next chart offers a different view. Below are these strikeout and innings totals for the past ten seasons (2010-19), given as decade-over-decade percentages.

There are a couple points to unpack here. First, qualifying starters had a brief resurgence at the beginning of this decade, as compared to ten years prior in the early 2000’s. Since then though, their ranks have tapered fairly consistently. Decade-over-decade the other achievements have undergone a more drastic fluctuation. The number of 200 inning pitchers have more than halved (DoD) in the past five years; meanwhile, 200 strikeout pitchers have doubled (or more) decade-over-decade four of the past five years.

Today, strikeouts are a preferred means to an end; of the 15 pitchers who pitched 200 or more innings in 2019, just 3 did not record 200 strikeouts while doing so: Zack Greinke,  Marco Gonzales, and Jose Berrios. Meanwhile, Max Scherzer, Charlie Morton, Matthew Boyd, and Robbie Ray each fell short of 200 innings, but struck out more than 235 batters apiece.

So, if you’re to take anything away from what’s written above, it might be that we value what is objectively arbitrary, or round, when it comes to milestones in baseball. In the case of Mike Minor, going out of one’s way to reach an arbitrary goal was taken offense to. In the case of Buehrle, it was (at least to my knowledge) not. Strikeouts are sexy, innings pitched are less so. What isn’t arbitrary though is the frequency in which either of those achievements are currently attained.