The Universal Designated Hitter
Since 2022 pitchers do not bat in either league, which ended the sport's oldest structural difference.
What it actually is. The designated hitter bats in place of the pitcher and does not field. The American League adopted it in 1973 and the National League did not, so for nearly fifty years the two leagues played different games. Since 2022 both use it. A club may also use the Ohtani rule, keeping a pitcher in as the designated hitter after he leaves the mound.
What somebody who knows the game gets out of it. The strategic loss is real and worth naming: the double switch, the decision whether to pinch hit for a pitcher in the sixth, and the sacrifice bunt by the number nine hitter all largely disappeared with it. What was gained is a lineup with no automatic out, which raised offense slightly and removed the injury risk of pitchers running the bases. The argument was never about which was better baseball, it was about which tradition mattered more.
The numbers worth knowing. Pitchers hit around .110 in their final seasons of batting. The change is worth roughly a tenth of a run per game in the National League.
What people get wrong about it. A club can lose the designated hitter mid game. If the DH takes a defensive position, the spot is forfeited and the pitcher must bat, which is a rule that catches out managers roughly once a season.
At Little League and travel ball. Youth rules on the DH, the extra hitter and the continuous batting order differ by sanction and are one of the most confusing areas for new travel families. Batting the roster, using an EH, and using a DH are three different things, and the travel section of this site compares them directly.
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