The Captain's Blog

Strikeouts have taken over baseball like a plague. Or is it an epidemic? How about a crisis? All across the majors, “three strikes you’re out” has become an unwelcome routine at the old ballgame, and, early indications suggest there is no end in sight. Can baseball survive this assault on the aesthetic quality of the game, or will inactivity finally be the death knell that the sport has long avoided?

Strikeouts are boring. That’s the underlying concern of many who fear their seemingly interminable proliferation. But, have strikeouts really had a negative effect on the entertainment value of the game?  To answer that question, we need to examine the impact that the increased level of strikeouts has had on both positive and negative offensive outcomes, and then consider whether those changes are more or less pleasing from a spectator’s perspective.

Strikeout Rate vs. wOBA, 1989-2018

Source: fangraphs.com

Over the last 30 years, strikeouts and offensive production (wOBA) have had a moderate negative correlation, but a plot of both measures defies a discernible pattern. In fact, aside from strikeout and home run rates, the seasons before and after the infamous steroid era peak look very similar. So, if baseball is suffering because of a decline in offense, strikeouts aren’t the culprit. And, if strikeouts really are a plague, it’s not because they have suppressed run scoring to an unprecedented level.

Base Hit Rates by Type, 1989-2018

Source: fangraphs.com

What about how runs are scored? As strikeouts have risen, the rate of home runs have increased at the expense of singles. Overall, that has meant more runners jogging around the bases instead of sprinting from first to third, but is that change enough to cause some fans to lose interest? Translating those aggregate numbers into real outcomes might help answer the question. If the single and HR rates from 1989 were applied to the number of 2018 plate appearances, there would have been 2,067 fewer homers (0.85 per game) and 3,855 more singles (1.6 per game) last season. Even for the most ardent advocate of small ball, that shift doesn’t seem to rise to the level of an epidemic.

Strikeouts as a Percentage of All Outs Recorded, 1989-2018

Source: fangraphs.com

If the change in positive offensive outcomes hasn’t been substantial enough to change baseball’s aesthetic, what about the type of outs? The increasing rate of strikeouts relative to plate appearances is well documented, but when considered as a percentage of outs (innings pitched x 3), the jump looks even more stark. In 1989, one out of every five outs was a strikeout. Today, it’s closer to one out of every three. Assuming all other forms of non-batted ball outs are stable (e.g., double plays, caught stealing, pickoffs, outs on bases; from 2015 to 2018, these rates were relatively constant), there are about seven fewer defensive plays in a nine inning game. That seems to validate concerns about baseball become more stationary, but does that necessarily make today’s game less exciting?

What exactly are strikeouts replacing? Those who lament the meteoric increases in strikeout rates seem to assume that the inactivity of a third strike is depriving the game of a well struck ball or a sparkling defensive play. The latter assertion is hard to test, but using Baseballsavant’s classification for contact, which is based on the probability of a batted-ball event having a favorable outcome, the former supposition looks to be untrue.

Batted-Ball Outs Classified by Quality of Contact, 2015-2019YTD

Note: See here for a detailed explanation of the Barrel metric. Batted outs in the Statcast database may not equal the recorded total for the season.
Source: baseballsavant.mlb.com

From 2015 (the beginning of the Statcast era) to 2018, the percentage of batted ball outs has declined from about 66% to approximately 61.5%. However, those outs classified as “Barrel” or “Solid” increased by nearly two percentage points, leading to 1,000 more well struck outs. Meanwhile, the decline in the “Flair/Burner” or “Poorly” categories has resulted in 4,011 fewer batted ball outs classified as weak contact (i.e., in most cases, routine outs). Interestingly, that decrease nearly accounts for the 3,761 extra strikeouts recorded over the same span, suggesting that strikeouts are not exactly taking the place of exciting plays. What’s more, the increase in hard outs is nearly 60% of the decline in singles. If these expected hits are being turned into outs because of other factors, such as defensive shifts, strikeouts would not only be absolved of blame for their decline, but, under more static circumstances, there might actually have been an increase.

Batter Outcomes: 2015 v. 2018

Note: Hard outs are the sum of the baseballsavant Barrel and Solid metric. Weak outs represent Flair/Burner and Poorly categories. Batted outs in the Statcast database may not equal the recorded total for the season.
Source: baseballsavant.mlb.com

Without accurate classification data for earlier periods, it’s hard to determine whether the shift in the quality of batted ball outs is both a sustainable trend and one that has resulted from the increasing strikeout rate. However, the data since 2015 does mitigate some of the concern about too many strikeouts having a negative impact on the aesthetic quality of the game.

In summary, since at least 2015, baseball has seen: (1) less contact overall; (2) higher exit velocities on batted balls that are turned into outs; and fewer singles and more home runs when an out isn’t recorded. Granted, it’s impossible to know the extent to which the increase in strikeouts has led to these other trends, but regardless of the reason, these shifts might, on balance, be making the game more exciting, and that’s granting the questionable premise that the strikeout is a boring play. After all, if the cure for seeing too many hitters blown away by a 100 mph fastball or stunned into submission by a devastating hook is a heavy dose of slow grounders and routine fly balls, the plague might not be so bad.