Baseball

Baseball is almost perfectly suited to review technology, because nearly every call is a question about where an object or a body part was at a specific instant. Was the foot on the bag before the ball arrived? Did the ball clear the wall? Was it fair or foul?

Replay arrived in 2008 for boundary calls and expanded in 2014 into a manager's challenge covering most of the sport. It is uncontroversial, and the reason is that it answers factual questions with correct answers.

The exception is the one that matters most. Balls and strikes are still called by a human, several hundred times a game, and the strike zone is defined partly by the batter's stance — from the midpoint of the torso to below the kneecap, as the batter is prepared to swing. That is a zone that changes shape for every hitter and moves as they move.

Automated ball-strike systems exist, have been trialled extensively in the minor leagues, and are technically capable. The sport has not adopted them at the top level, and the argument against is not accuracy. It is that framing — a catcher's skill in receiving a borderline pitch so that it looks like a strike — is regarded by much of the sport as a real skill worth preserving, and automation would delete it.

That is a genuinely unusual position on this site. Tennis removed its line judges because the machine was better. Baseball has a machine that is better and has declined so far, because it values something the machine would remove.

Baseball is intensely popular in a small number of places and almost absent from the rest of the world, which puts it alongside cricket as one of the two most geographically concentrated sports here — and the two maps do not overlap at all.

The United States, Japan, South Korea, Taiwan, Cuba, the Dominican Republic, Venezuela, Puerto Rico, Mexico, Panama and Nicaragua account for essentially all of it. That distribution follows American military and commercial presence in the late nineteenth and twentieth centuries almost exactly, in the same way cricket's follows the British Empire.

The Caribbean and Central American nations are the most productive relative to population by a wide margin, and the pathway there runs through academies funded by American professional clubs — a recruitment structure with no parallel in any other sport on this site, and one with a documented history of abuses that the league has regulated only recently.

Japan's is the other case worth recording, because it is the one place where a professional structure developed independently and produced a genuinely different version of the sport: different ball, different strike zone in practice, and a distinct playing culture. Nippon Professional Baseball is not a feeder league.

The Olympic consequence is awkward. Baseball has been on and off the programme repeatedly, and the reason it keeps being dropped is that its best players are under contract to a league that will not release them mid-season. A sport whose rules are made by a league also has its Olympic participation decided by one.

Baseball's origin story was invented, and the invention is more interesting than the truth.

The Doubleday myth — that Abner Doubleday devised the game at Cooperstown in 1839 — was manufactured by a commission set up in 1905 specifically to establish that baseball was American rather than descended from English bat-and-ball games. It was not true. Baseball descends from rounders and similar games, and the first substantial codification is the Knickerbocker rules of 1845 in New York.

What the myth tells you is that this sport has always understood itself as a national institution first and a game second, which is why its rule changes are argued about in a register no other sport here uses.

The genuinely inventive parts arrived over the following decades and are all about geometry. Ninety feet between bases is the number the sport is proudest of, because it makes a routine ground ball an almost exactly even race between runner and throw. Sixty feet six inches from mound to plate was settled in 1893 and has not moved since.

The National League was founded in 1876 and the American League in 1901, and the two ran as rivals before merging into one competition — a structure that would matter enormously seventy years later, when one of them adopted a batting rule the other refused for forty-nine years.

Baseball's equipment is regulated tightly at the professional level and loosely everywhere else, and the sport is unusually relaxed about the consequences.

The bat. Professional baseball requires a single piece of solid wood. College and amateur baseball permit aluminium and composite bats, which are lighter, more forgiving and produce faster exit velocities — and the sport does not pretend the statistics travel between the two. A college batting average and a professional one are not compared, and nobody proposes that they should be. That is the correct handling of a comparability problem, arrived at without anyone calling it one.

The ball. The recurring controversy that has never become a rule change. Home run rates have moved sharply between seasons in ways that correlate with changes in the ball's construction and aerodynamic behaviour, and the sport has been accused repeatedly of altering it, deliberately or otherwise. The specification — weight, circumference, construction — has not changed. Whether what is made to that specification has, is the argument.

That is the exact inverse of every other equipment story on this site. In athletics and swimming, the specification was outrun and had to be rewritten. In baseball, the specification has held and the object may have moved inside it.

The glove grew steadily through the twentieth century and is now specified by size. Protective equipment followed injury: batting helmets became mandatory in the 1970s, and helmets with extended jaw protection followed later incidents.

Baseball's rules are made by a league, not a federation, and that is the structural fact behind everything on this page.

The WBSC governs internationally and runs the Olympic tournament. Major League Baseball governs itself, and every rule change recorded here — the mound, the designated hitter, replay, the pitch clock — was an MLB decision. This is basketball's arrangement taken further: at least FIBA and the NBA converge over time, whereas baseball's international body largely follows the league.

The internal split is the more remarkable governance fact. From 1973 to 2022, the American League used a designated hitter and the National League did not. One sport, one championship, two batting rulebooks, for forty-nine years — including in the World Series, where the rule in force depended on which park the game was in.

No other sport on this site has done anything comparable. It persisted because the two leagues had separate identities and separate administrations long after they had become one competition, and because each side regarded the other's rule as a departure from what baseball was.

The other permanent feature is labour. Baseball has the most organised player body in American sport and the most contested history of stoppages, and rule changes go through collective bargaining. The 2023 pitch clock was negotiated rather than imposed, which is why it arrived as a package with the shift restriction and larger bases.

1968, the Year of the Pitcher. Scoring collapsed. Bob Gibson recorded an earned run average of 1.12; Carl Yastrzemski won a batting title at .301, the lowest figure ever to do so. The sport concluded that pitching had won too completely and, within months, lowered the mound from fifteen inches to ten and shrank the strike zone.

That is a governing body reaching into the geometry of the field to change a statistical outcome, and it worked immediately. It also severed every offensive statistic in the sport.

The designated hitter, 1973. Adopted by one league, refused by the other, and the split lasted until 2022. For half a century, comparing an American League pitcher's earned run average with a National League pitcher's was comparing performances under different rules, and everyone did it anyway.

The shift. Through the 2010s, teams used batted-ball data to position fielders where a particular hitter actually hits the ball, and batting averages on ground balls fell accordingly. It was legal, effective, and the product of analysing the sport's own records. In 2023 it was restricted.

This is the same act as basketball banning zone defence and football's 1925 offside change: a rule written against a way of playing that was working too well. The objection — that it penalises teams for thinking correctly — is the same objection in all three cases.

Time. Game length had risen for decades while the ball was in play for less of it. A sport that had defined itself by having no clock put one on the gap between pitches in 2023, and the games got substantially shorter immediately.

Recorded as unsettled.

Automated balls and strikes. The technology works and has been trialled for years. The sport has not adopted it at the top level, and the argument is not about accuracy — it is about whether pitch framing, a real and trained skill, should continue to exist. Baseball is the only sport on this site actively declining a working automation for a stated reason other than error rate.

Whether the shift ban was right. Restricting where fielders may stand legislates against a conclusion teams reached by analysing the sport's own data. Supporters say it restored a balance the data had destroyed; opponents say a sport should not punish correct thinking. The same argument attaches to basketball's illegal-defence rules and football's 1925 offside change, and it has never been settled in any of them.

The ball. Home run rates keep moving in ways that the specification does not explain, and the sport has never satisfactorily accounted for it. Until it does, every power record of the last decade carries an asterisk nobody has written down.

Pitcher injuries. Elbow reconstruction is close to a routine career event, velocity keeps rising, and no rule has ever been written about it. This is the largest unaddressed problem in the sport and the one this site finds most striking: a governing body that will move the pitching mound to raise scoring has not moved anything to stop its pitchers breaking.

Olympic participation. The sport returns in 2028 without a settled answer on whether its best players will be released to play.