The designated hitter rule changes one of baseball’s most basic lineup relationships: the pitcher no longer has to bat simply because he is on the field. In Major League Baseball, a team can name a designated hitter, or DH, to take the pitcher’s place in the batting order while the pitcher continues to play defense. That sounds simple, but substitutions, defensive switches, and two-way players can make the rule feel more complicated once a game is underway.
What the designated hitter does
The DH is an offensive lineup position. The player bats in a fixed spot in the order but normally does not play defense. The pitcher still pitches, fields his position, and remains one of the nine defensive players.
Under the current designated hitter MLB rule, both American League and National League teams use the DH. The American League first adopted the rule in 1973. The National League used a universal DH in the shortened 2020 season and then adopted it across the league beginning in 2022.
A standard MLB lineup can therefore involve 10 starting players: nine defensive players plus a DH who bats for the pitcher. The pitcher is not part of the batting order while a separate DH is being used.
How the DH is placed in the batting order
The manager must name the DH before the game. The DH occupies one specific batting-order position, just like any other hitter, and that position does not move to match different pitchers. Relief pitchers can enter without changing the DH’s place in the order.
The starting DH generally must take at least one plate appearance unless the opposing team changes pitchers before that first turn at bat. If a team chooses not to name a DH before the game, it cannot add one later. That matters because the DH is not a flexible bench slot that can be activated whenever a manager wants.
What happens when the DH is substituted
A team can pinch-hit or pinch-run for its DH. The substitute then becomes the new DH and remains in that same batting-order position. As with other MLB substitutions, a player who has been removed from the game cannot return later.
Managers often use this flexibility to improve a matchup. If a right-handed DH is due to face a dominant right-handed reliever, for example, the manager might send up a left-handed pinch-hitter. That hitter becomes the DH if he stays in the game.
When a team loses the DH
The most confusing part of the DH rule baseball fans encounter is that certain defensive moves eliminate the DH for the rest of the game. If the player serving as DH moves to a defensive position, he stays in his batting-order spot, but his team can no longer use a DH to bat for the pitcher.
The DH is also lost if the pitcher moves from the mound to another defensive position or if the current pitcher bats or runs for the DH. Once the DH role has been terminated, the team cannot restore it later in that game.
A practical late-game example
Imagine a team’s first baseman is injured in the eighth inning and the only available replacement is the current DH. The manager can move the DH to first base, but that decision ends the team’s use of the DH. The manager may later need to pinch-hit for a pitcher and then make another pitching change. A simple defensive switch can therefore create several later decisions.
For readers learning how the batting order fits together, a useful next topic is baseball batting order rules. Another natural follow-up is how baseball substitutions work.
The special rule for a starting pitcher who also serves as DH
MLB added an important exception in 2022 for a starting pitcher who also bats for himself. The rule is often associated with Shohei Ohtani, although it applies generally. A starting pitcher can be listed both as the pitcher and as the DH, treating those roles separately.
If that player is removed as the pitcher, he can remain in the lineup as the DH. If he is replaced as the DH, he can continue pitching but no longer hits for himself. This changed the old pitcher batting rule because a two-way star no longer has to leave the batting lineup just because his pitching appearance has ended.
The exception is tied to the starting pitcher being listed in both roles from the beginning. It is different from simply moving an ordinary DH to the mound later, which can create different substitution consequences.
Why the universal DH changed MLB strategy
The universal DH removed many old National League decisions built around weak-hitting pitchers. Managers no longer have to decide whether to let a pitcher bat in order to keep him on the mound, and double-switches are far less central to lineup management.
Strategy has shifted toward roster construction and offensive matchups. Teams can use the DH for a power hitter, rotate regular players through the spot to reduce defensive wear, or keep a strong bat in the lineup while using a better defender in the field.
The role can also help clubs manage veterans or players returning from injury by reducing defensive workload without removing their offense. A related strategy topic is how MLB managers use pinch hitters and defensive replacements.
Frequently asked questions
Who does the designated hitter bat for?
In MLB, the DH normally bats in place of the pitcher. The pitcher continues to play defense but does not bat while the DH role remains active.
Can a designated hitter play defense later in the game?
Yes. A DH can move to a defensive position, but doing so causes the team to lose the DH for the rest of that game. The player continues hitting in the same lineup spot.
Can a team change its DH during a game?
Yes. A pinch-hitter or pinch-runner can replace the DH. That substitute then becomes the DH and takes over the same batting-order position.
Can the starting pitcher also be the DH?
Yes. Under the rule introduced in 2022, a starting pitcher can also be listed as the DH. If he later leaves the mound, he can remain in the game as the DH.
What to remember about the designated hitter rule
The easiest way to understand the designated hitter rule is to separate offense from defense. The pitcher handles the pitching job, while the DH takes the pitcher’s place in the batting order. Substitutes can replace the DH, but certain defensive switches can end the role entirely. The starting pitcher/DH exception adds flexibility for two-way players, while the universal DH has made MLB lineups consistent across both leagues. Once those principles are clear, most in-game DH decisions become much easier to follow.