The designated hitter (DH) feels like it’s always been part of baseball, but it didn’t arrive in the majors until 1973 in the American League—nearly a century after professional baseball began. This single rule change sparked one of the sport’s most enduring debates and fundamentally altered how the game is played. Pitchers who once batted around .150 average in the 1960s were suddenly replaced by actual hitters, and the game became measurably more explosive.
Why pitchers had to bat: the early baseball logic
For decades, baseball had nine fielders and nine batters—no exceptions. Pitchers took their turn at the plate like everyone else. In baseball’s infancy, this made sense; pitchers threw fewer innings and weren’t yet specialized athletes. But as the game evolved, pitchers became worse hitters. By the 1960s, the gap was staggering: a typical pitcher batted 200+ points below league average, turning the pitcher’s spot into an automatic out.
A radical idea takes 20 years to gain traction
The DH concept had been floating around since the 1950s, but the National League rejected it outright as «un-baseball.» They argued it destroyed strategy and the purity of the game. The American League, more experimental, decided to try it in 1973. The results were immediate: AL teams averaged 4.37 runs per game in 1973 versus 3.81 in the NL. Games were more exciting, fans loved the offensive fireworks, and attendance climbed. The experiment became permanent.
The first official DH: a delayed honor
While some players had batted as designated hitters in exhibition games, Edgar Martínez of the Seattle Mariners is credited as the first official DH in regular-season play on April 6, 1989—though technically the rule began in 1973. Martínez’s career as a DH became the gold standard: two-time batting champion, .312 career average, and a Hall of Fame case built largely on his role as a pure hitter.
The National League holds out for 50 years
Here’s where it gets wild: the National League didn’t adopt the DH until 2022. For nearly five decades, NL pitchers still had to bat, making the two leagues fundamentally different. This created bizarre situations where a player could be a DH in the AL but a position player in the NL. Finally, in 2022, MLB unified the rule. The NL’s resistance had become untenable—it was costing them offensive excitement and competitive balance.
How the DH changed baseball’s numbers
| Metric | American League (with DH since 1973) | National League (without DH until 2022) |
|---|---|---|
| Average runs per game (historical) | 4.2 | 3.9 |
| Team home runs per season (2019 avg) | 215 | 198 |
| Pitcher RBIs per season (historical avg) | N/A | 0.3 |
FAQ
Why did the National League resist the DH for so long?
Traditionalists viewed it as a betrayal of baseball’s essence. They believed the game required nine positions and that managerial strategy—deciding when to pinch-hit or pull a pitcher—was sacred. But offense and attendance numbers eventually won the argument.
Can a team choose not to use a designated hitter?
Technically yes, though it’s nearly extinct in modern baseball. A manager can let the pitcher bat, and it happens occasionally in rare circumstances, but it’s practically unheard of in the majors.
Has the DH made baseball better or worse?
The stats say better: more runs, more home runs, more action. Purists counter that it eliminated strategic depth and the drama of pitcher changes. Both sides have a point, but the fans voting with their wallets chose offense.
