The Biggest Rule Changes in Baseball History

Baseball is a very old-time American sport that’s been around for two centuries, although Americans love it all the same. However, several changes have been made to the rulebook over the years, particularly in Major League Baseball (MLB), that affected how the modern game is played.

The most crucial baseball rule changes were made early on, while others were finalized more recently. A lot of these reforms were made from both the perspective of the league and culture as a whole, so regardless of how you may feel about some of them, they’ve shaped the way baseball is played today.

9-Inning Rule (1857)

Believe it or not, the ancient game of baseball would often go longer than 9 innings. Before 1857, baseball games would only end after the inning where a team reached 21 runs. So, the game’s length was directly related to how quickly you can run home 21 times, and after 12 years of being untouched in the Knickerbocker Rulebook, baseball saw its first implementation of the 9-inning game rule.

Based on how good pitchers are today, we can all thank rulemakers for adding the 9-Inning Rule to the MLB’s rulebook.

Foul Balls are Strikes (1901)

Another surprising rule to modern baseball fans is that foul balls didn’t always count as strikes. It wasn’t until 1901 that the National League started giving strikes to a batter with less than 2 strikes already at bat and 1903 for the American League.

This immediately impacted the nature of strikeouts, making them more of a necessity to win. To win a battle of strikeouts, you need a great pitcher, so after 1903, the foul ball counting as a strike led the way to the era of dominant pitchers.

Designated Hitters (1973)

Over 70 years since the emphasis on pitching and the designated hitter rule finally got implemented into the MLB. In 1973, the league created the Designated Hitter (DH) rule, allowing another player to bat in place of the pitcher for the entire game but not play in the outfield.

While mainly created to preserve the health of pitchers (once again, the prize possession in baseball), the DH rule was extremely unique and changed the way baseball would be played.

Free Agency (1975)

It may have taken longer than it should’ve, but by 1975, all players in the MLB had the right to free agency. This means that players with expired team contracts are not required to re-sign with the same team. Free agents are eligible to join new teams and negotiate for different salaries at their discretion.

Typically, in modern MLB, there are only several windows a year where transfers and trades are available. While this doesn’t necessarily affect a baseball game specifically, the rule affects the longevity, morale and salary of players and managers altogether.

Pitch Clock (2023)

Many years have passed since most of these vital rule changes have been implemented in the MLB, and while changes are made every year, they are not normally done with such a high magnitude. By 2023, to quicken the sport’s pace, the MLB implemented mandatory 30-second pitch timers between batters.

There’s also a timer between pitches, 15 seconds with the bases empty and 20 seconds with runners on. This rule change was essentially made in the 21st century to hurry up the pace of the game, which was scrutinized over several decades for being elongated to include more ads, commercials and waiting time rather than just playing the game.