Baseball Roster Rules

Managing a baseball team is one of the trickiest things to do in all of sports. One of the most difficult duties for a manager is dealing with a roster. There are many ways that a roster may change in a given season between injuries and acquisitions. Most roster moves often depend on contracts and salaries.

  1. Rosters

    • Major League Baseball rosters involve two types–the 25-man roster and the 40-man roster. An MLB 25-man roster includes the active players that are eligible to compete on the team during the season. The extra 15 players are players that can include minor leaguers or injured players. The 25-man roster is the major league roster for the five months of the regular season.

    Trade and Outright Release

    • A trade is when players are swapped from one team to another. All trades involving money must first be agreed to by the MLB commisioner's office. Teams have until July 31 to make these trades. Teams also might cut players from their rosters. That can involve an unconditional release, an irrevocable outright or revocable major league waivers. A player outrighted to the minor leagues is paid under the terms of a guaranteed contract.

    Disabled List

    • When a player is injured, he may be placed on the 15-day or 60-day disabled list. When that player is moved to the DL, another may be added to the 25-man roster from the extra players on the 40-man roster. If the club wants to add a player not from the 40-man roster, they must purchase that player's contract and add him to the 40-man roster and drop another.

    Designated for Assignment

    • If a team wants to remove a player from the 40-man roster, it can designate him for assignment. Players that are on a 40-man roster with three years major league service can refuse an outright assignment and choose to become a free agent. The player can be put on waivers, where any team may claim him and has to pay him the remainder of his salary. If he clears waivers, he may accept an option to the minor leagues. If he declines his option, the team has 10 days to either trade him or offer the player his outright release.

    Waivers and Waiver Trade Deadline

    • When a player is put on unconditional waivers, he may be claimed by any team and that team may simply take him. However, after July 31, it becomes revocable waivers. In revocable waivers, other teams may claim a player, then that player's original team may elect to keep him, trade him to the claiming team or, according to the CBA Baseball website, "allow the player to be claimed, which results in the claiming team paying the remainder of the player's current contract." However, if a player clears revocable waivers, he may then be traded to other teams.

    Roster Expansion

    • On Sept. 1, all major league rosters are expanded to 40 players. Teams may allow as few or as many of their extra 15 players to come up as they deem necessary. However, players who are called up after Sept. 1 are ineligible for postseason play, unless they have been on the major league roster prior to Sept. 1 or if they are replacing an injured player.