|Babe Ruth Player Substitution Rules
The EH. Ten players are permitted to be in the game at any given time. Being in the game means having a place in the batting order and being assigned either to one of the usual nine positions on the field or to the position of “Extra Hitter” (EH). The EH is considered to be in the game and has a place in the batting order, but the EH does not have a defensive position on the field.
Defensive Changes. The ten players who are in the game can be moved to any defensive position at any time. For example, the manager can have the shortstop and the right fielder swap positions. This does not change their position in the batting order. The manager can also have the EH swap defensive positions with another player, again without changing their position in the batting order. Some managers like to avoid having the same player be the EH for two consecutive innings so that players take turns “missing” a defensive half inning in the field. This may give the appearance that players are going in and out of the game every inning, but in reality the same ten players are in the game and the batting order remains unchanged; different players are just being assigned to be the EH.
Substitutions. If more than ten players are on a team, then some players will have to substitute for each other during the course of the game. For example, if 11 players are present, then one player will be out of the game at any given time. In this case, two players would remain in the dugout during a defensive half inning: the EH (who is in the game but not playing a defensive position) and the player who is not currently in the game. The EH may play a defensive position the following inning, but the substitute only begins batting and playing a defensive position after they are put into the game.
Re-entry. When a starting player has come out of the game, they may re-enter the game but they must replace the same player who replaced them (and bat in the same position in the batting order where they were batting originally). The player coming back out of the game does not play for the rest of the game.
Minimum Play Requirement. Managers are required to play each player for a minimum of nine defensive outs and one at bat (in a game in which at least five innings are played). The manager may choose to have a starting player play only part of their minimum play requirement before coming out of the game (in order to get a substitute into the game sooner, for example). In this case, the starter will re-enter the game to complete their playing time after the substitute has played at least their minimum requirement.