Baseball does not change.
Yes, the rules change; the bats change; the fields, the uniforms and the broadcasts change. The pitchers throw differently, and the hitters don’t swing the same. The gloves have changed shape, and the umpires call the games in a new way.
But, since 1871–since before 1871–the ancient Spirit of Pitchers has sat in the same spot, unmoving, across from the timeless Spirit of Batters, and they have played their unending game of chess in the exact same way, no change.
Consider Washington D.C.’s mild afternoon on April 10, 1928.
Bill Regan steps to the plate with two runners on base. It is Opening Day. The crowd, crowned with derbies and garnished with handlebars, rises to its feet. The 5-foot-10 second baseman is about to have his best season ever, at one point hitting two home runs in a single inning–the lone Red Sox player to perform that feet until Ellis Burks repeats it 61 years later. But today, a clear day in the nation’s capital, he won’t have any homers.
The towering 6-foot-1 Milt Gaston–pitching against his brother-in-law, Red Sox starting pitcher Danny MacFayden–delivers the pitch, and Regan slaps it into play and begins a mad dash around the diamond, clearing the bases with a roaring triple.
The first game of the 1928 season ends 7-5, Red Sox over Senators, and–more appropriately–with a tally of one triple and zero home runs. The 1928 season is the final season in baseball history in which hitters were considerably more likely to hit triples than homers. In 1931, triples would have a final gasp–1,070 triples against 1,069 homers–but from then on, the four siblings would now be ordered: singles, doubles, homers, then triples.

Singles and triples have been on steady decline as homers tick upwards.
What caused the decline in triples? Changes in the rules? Different ballpark dimensions? New approaches to hitting, a new calculus for base running?
The answer: Yes. Yes to those things, and yes to countless other factors.
In 2016, hitters had the lowest rate of triples per at-bat in major league history spanning back to 1871. In 2017, they hit the second-lowest rate of triples. Also in 2017: the lowest rate of singles in baseball history and the highest strikeout rate ever recorded.

While the rate of doubles has fluctuated over the years, homer and triples have taken steady, opposite paths.
When the baseball world had, oh, let’s say a kind of panic attack about the spike in home run rates starting in 2016, we spent perhaps too little time talking about the massive decline in other outcomes: the placement of triples on the endangered species list and the rapid decline in singles.
The sport of baseball is at its core a 150-year-old war of batters versus pitchers. For the first few decades of the sport, that battle was not explicitly acknowledged; pitchers were supposed to throw hittable pitches and batters could request pitches high or low. But the tension of batter versus pitcher still existed, even in those earliest times. The first paid professional ball player, Jim Creighton, was notorious not just for exploding his abdomen on a gargantuan and ultimately fatal home run swing, but also for reputedly throwing his pitches using a subtle and quite illegal wrist snap in his delivery.
This tug of war between hitters and pitchers had its biggest early gains and losses in the rule book: Pitchers eventually were allowed to snap their wrists during throws (1872) and then eventually throw overhand (1883). Then batters were no longer allowed to call for high or low pitches (1887), and the bats couldn’t be flat on one side, and the pitcher’s mound was moved back 10 more feet (1893).
Most of these changes helped the pitchers and wrangled out-of-control scoring into a more manageable pace.

As the rules of the game evolved, the run-scoring rates per team went from over eight runs per game to the modern four runs per game.
The next stage of the war took place in the ballparks. In 1925, Major League Baseball league determined the minimum home run distance to be 250 feet. In 1959, the minimum dimensions become more specifically 325-400-325 in the left-center-right fields. Each of these shifts–and the ongoing tweaks to ballpark design, from foul ground size to wall height to playing surfaces–have altered the interactions between pitcher and hitter, emphasized different abilities and talents, changed the nature of the unending war.
Technology and sports medicine became another battlefield. New fitness regimes altered the way players prepared for games and seasons. Weightlifting and calisthenics went from out of fashion to recommended to mandatory. Pitch counts and bullpens began to maximize pitchers’ physical output. Specially designed pitching machines helped players identify pitches by spin. Motion tracking tech gave hitters a chance to study their swing patterns.
Racial integration; performance enhancing drugs (PEDs) such as cocaine, greenies (amphetamines) and steroids; the influx of international players–these are forces that impacted both sides of the battle by possibly equal measures. The so-called “Steroid Era” is notorious for home runs, high ERAs and batters dominating pitchers. The flaw in this narrative, however, is the slew of pitchers who have admitted or been strongly suspected of steroid use.
If increased strength gave hitters such a decisive advantage, then why did pitchers continue to dope? If pitchers throwing hard led to more home runs, then why in the mini-Dead Ball trough of 2010 to 2015 were home runs scarce and pitches faster than ever? And more importantly, why are there more home runs and almost just as high ERAs now, in an era ostensibly not marred by rampant PED use? Has the modern batter found his way around PED testing or some other advantage in a way that affects him more than it affects pitchers?
In the peak of the Steroid Era, the 2000 season, the major league run average (RA9) was 5.20, and in 2017 it was 4.77. This is noteworthy because that same pairing of seasons when examined in ERA (4.77 in 2000 and 4.36 in 2017) has a narrower gap. When we ignore runs scored with the assistance of sloppy defense, the Steroid Era looks much closer to our modern run environment. In fact, since the peak of the Steroid Era, the gap between ERA and RA9 has been ever-narrowing. The narrowing distance between Run (R) rates and Earned Run (ER) rates help illustrate this change. The Steroid Era could just as easily have been called the “( ಠ ʖ̯ ಠ) Defense Era.”

Apparently guys like Manny Ramirez weren’t the best fielders.
Transport a modern Yankee into 1922; let’s take Brett Gardner and stuff him in a time machine. He now faces 80-mph pitches and a defense wearing essentially oven mitts. He must trade in his 33-inch, 30.5-ounce Mizuno Pro for a 35-inch, 40-ounce bat with a thicker handle–and defend a strike zone that goes all the way to tops of his shoulders. He now calls the 279-483-253 insanity that is the Polo Grounds home field. What happens to his offensive output as he faces in-shoots, spitballs and scuffed and torn leather spheroids that resembled baseballs five innings earlier? We have asked him to play an almost entirely different sport, even though Gardner himself is considered by many to be a throwback type of player.
Bring my favorite classic player–Mordecai “Three Finger” Brown–into the modern Cubs rotation and what happens? He is no longer impressive with his upper-80s fastball; his hard-snapping curveball, suspected by some to be the first split-finger fastball, is quite possibly no longer a novelty; and what’s more: The ball isn’t made of horse hide anymore (and is much more lively), center field is 160 feet closer, and the mound is five inches lower.
The 5-foot-10 pitcher might struggle to find the smaller strike zone, and with “neighborhood plays” at second base gone in favor of the cold scrutiny of instant replay, as well as a fresh, not-scuffed baseball in hand for each pitch, his curveball certainly will induce fewer double plays – even if he brings Tinker, Evers and Chance with him.
The hitters he faces are infinitely more willing to strike out, not content with choking up two inches and weakly hitting the ball into play in a pitcher’s count. Moreover, the calisthenics routine that may well have given him a critical edge in fitness in 1908 now barely qualifies as a warmup routine. But with modern workout routines and medicine, with a bullpen allowing him to throw harder through seven innings over five days, and with modern analytics giving him data on each batter in the lineup, and fewer hitters seeing him multiple times in a single season, much of his old job might now feel easier.
All of this is to say: The inner game of baseball, the tug-of-war battle between pitchers and batters, continues to reshape the game and redefine success. With each new era, little in the true nature of the game changes. And when I step back and examine this meta tension and look at the trends of the data, I am less inclined to believe juiced-ball theories or Steroid Era narratives.
Consider the National Football League. The strategy conversation over the last decade has focused around this common notion: “It is a passing league now.”
What made this sport, which was roughly based on rugby–a sport without a forward pass at all–become a game almost entirely focused on throwing the ball to a receiver down the field? The answer is fairly straightforward in football, so it makes it an easy example for this more complicated evolution process in baseball. In the NFL, rampant injuries encouraged first the legalization of passing and then the subsequent hyper regulation of tackling passers and pass catchers. But through all of this, from World War II to today, the average score in the NFL has remained about 20 points per team per game.
In the earliest days of football, back when it was primarily a collegiate sport, frequent on-field fatalities–yes, fatalities–caused then-President Teddy Roosevelt to intervene and demand colleges legalize the forward pass or risk the fury of his bully pulpit. At first, incomplete passes resulted in turnovers, then eventually that was softened to penalties, and then finally a loss of down (as it is today).
Injuries to quarterbacks like Joe Namath, Joe Theismann, Michael Vick and Ben Roethlisberger have resulted in a gradual overhaul to what is considered an acceptable tackle of a quarterback, such that now pass rushers may only aim for the space between the shoulders and thighs and cannot make hard contact with the quarterback after he releases the ball. The quarterback is also given protections when he runs, unlike running backs or wide receivers. And pass targets–once the object of brutal hits from linebackers and safeties–have received protection in the form of when and how they can be hit, touched or bumped. The advent of the pass interference penalty in 1978 irrevocably bent the game in favor of passing offenses over running offenses.

Per game touchdown rates shifted radically and definitively towards passing touchdowns since the 1970s.
This evolution within football was gradual and traceable. Within baseball, it is more difficult to trace, in part because the end points have not been as distinct. Preventing a defensive back from holding a receiver’s jersey helps all receivers universally because their object is to create separation between themselves and the defenders. But changing the dimensions of the Safeco walls does not necessarily increase Ichiro Suzuki’s home run output in 2012; in fact, it may have negatively impacted his ability to hit triples. It might help a fringe power hitter like Michael Saunders eke out a few more homers, but then it hurts speedsters like Chone Figgins and Suzuki from stretching a line drive into an extra-base hit.
In football, every wide receiver’s job is to get open and catch a ball. In baseball, successful hitters can thrive on walks and singles, drag bunts and slap hits, or doubles and homers.
Likewise, the advent of PITCHf/x as a tool for critiquing umpires may have bred a new hitting approach among hitters who once played more aggressively given the uncertainty of the ball-strike call. Coinciding with the fly-ball hitters’ revolution: the rapid decline in sinker usage. It was just a few short years ago the Cardinals seemed to have found that teaching mid-level starters a sinker or two-seam grip could turn them into All-Stars. Now, the groundball revolution that helped pitchers may have turned into the flyball revolution that increased major league power again and killed the seeing-eye single.

Perhaps as a reaction to the fly ball revolution, pitchers have steered away from sinkers.
League-wide sinker usage in 2016 and 2017, as defined by the Pitch Info identification algorithms, took its first dip beneath 20 percent. The sinking fastball is rapidly becoming a less important pitch than the slider.
I believe part of what we are seeing in the recent flyball and home run uptick (and singles and triples downtick) is a function of both evolving pitcher-batter strategies and external influences, such as owners preferring hitters’ parks over pitchers’ parks. And if the change in run environment is a function of evolving strategies, that means it is likely to change in the coming years.
In world of baseball fandom and in the subculture of baseball analytics, we sometimes have a tendency to get caught up in the micro changes in the league. When managers began using the Ted Williams shift on non-Ted Williams players in the early 2010s, it appeared the offensive depression would be the new normal, the future ad infinitum. But when hitters realized that the decreased value of ground balls made fly balls more valuable, the major leagues reoriented toward higher run scoring.
In some senses, yes, this is a “there is no spoon” argument. I am not presenting an engineering argument against the juiced-ball theory. I am not really even attempting to conclusively prove anything about juiced balls. But I am rather attempting to caution us to avoid headlines like this:
- “Use of defensive shifts in baseball is spreading — because it works”
- “Is the infield shift ruining baseball?”
- “Time for Major League Baseball to ban the infield shift”
Or bold claims like (now former) San Francisco Giants pitching coach Dave Righetti has figured out how to beat FIP. Because it might turn out to be a matter of changing park factors moreso than a revolution in coaching. Or maybe it was an adjustment to pitch sequencing combined with park factors?
But the truth is, through all of this, baseball abides.
References & Resources
- Pro Football Reference
- Ben Lindbergh, The Ringer, “The Juiced Ball Is Back”
- Scooby Axson, Sports Illustrated, “Dallas Keuchel: ‘Obviously, the Balls are Juiced'”
- Ben Lindbergh, The Ringer, “As Home Run Rates Rise, MLB Offers Evidence That the Ball Isn’t Juiced”
- Tom Verducci, Sports Illustrated, “Forget velocity, the curveball’s resurgence is changing modern pitching”
- Frank Jackson, The Hardball Times, “Touching ’em All Minus One: Romancing the Triple”
- Katie Zezima, The Washington Post, “How Teddy Roosevelt Helped Save Football”
- Zach Helfand, Los Angeles Times, “Use of defensive shifts in baseball is spreading — because it works”
- Jeff Wiser, Beyond the Box Score, “Is the infield shift ruining baseball?”
- Eric Holden, AXS, “Time for Major League Baseball to ban the infield shift”
- Jesse Wolfersberger, FanGraphs, “Dave Righetti: Lord Of The HR/FB Rate”
- Grant Brisbee, McCovey Chronicles, “The home run revolution has completely passed AT&T Park by”