Playing for Peanuts

[SanDiegoSteve]

This is the rule you are looking for in the OBR:

Rule 3.03

A player, or players, may be substituted during a game at any time the ball is dead. A substitute player shall bat in the replaced player’s position in the team’s batting order. A player once removed from a game shall not re-enter that game. If a substitute enters the game in place of a player-manager, the manager may thereafter go to the coaching lines at his discretion. When two or more substitute players of the defensive team enter the game at the same time, the manager shall, immediately before they take their positions as fielders, designate to the umpire-in-chief such players’ positions in the team’s batting order and the umpire-in-chief shall so notify the official scorer. If this information is not immediately given to the umpire-in-chief, he shall have authority to designate the substitutes’ places in the batting order.