To learn about our efforts to improve the accessibility and usability of our website, please visit our Accessibility Information page. Skip to section navigation or Skip to main content
Below is an advertisement.

Rules of Interest

Select a specific rule: Additional rules: Want the full Offical Rules?
Rule 2.00: The Strike Zone

The STRIKE ZONE is that area over home plate the upper limit of which is a horizontal line at the midpoint between the top of the shoulders and the top of the uniform pants, and the lower level is a line at the hollow beneath the kneecap. The Strike Zone shall be determined from the batter's stance as the batter is prepared to swing at a pitched ball.

Rule 3.01: Pre Game

Before the game begins the umpire shall:

  1. Require strict observance of all rules governing implements of play and equipment of players;
  2. Be sure that all playing lines are marked with lime, chalk or other white material easily distinguishable from the ground or grass;
  3. Receive from the home club a supply of regulation baseballs, the number and make to be certified to the home club by the Office of the Commissioner. Each ball shall be enclosed in a sealed package bearing the signature of the Commissioner of Baseball, and the seal shall not be broken until just prior to game time when the umpire shall open each package to inspect the ball and remove its gloss. The umpire shall be the sole judge of the fitness of the balls to be used in the game;
  4. Be assured by the home club that at least one dozen regulation reserve balls are immediately available for use if required;
  5. Have in his possession at least two alternate balls and shall require replenishment of such supply of alternate balls as needed throughout the game. Such alternate balls shall be put in play when:
    1. A ball has been batted out of the playing field or into the spectator area;
    2. A ball has become discolored or unfit for further use;
    3. The pitcher requests such alternate ball.
  6. Ensure that an official rosin bag is placed on the ground behind the pitcher's plate prior to the start of each game.
Rules 3.03 & 3.06: Player Substitutions
3.06

The manager shall immediately notify the umpire-in-chief of any substitution and shall state to the umpire-in-chief the substitute's place in the batting order.

3.03

... 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.

Rule 8.02: Throwing at the Batter

Rule 8.02 states as follows:

  1. The pitcher shall not intentionally pitch at the batter.

    If, in the umpire's judgment, such a violation occurs, the umpire may elect either to:

    1. Expel the pitcher, or the manager and the pitcher, from the game, or
    2. may warn the pitcher and the manager of both teams that another such pitch will result in the immediate expulsion of that pitcher (or a replacement) and the manager.

    If, in the umpire's judgment, circumstances warrant, both teams may be officially "warned" prior to the game or at any time during the game.

    Rule 8.02(d) Comment: ... To pitch at a batter's head is unsportsmanlike and highly dangerous. It should be - and is - condemned by everybody. Umpires should act without hesitation in enforcement of this rule.

As the Rule itself implies, the first question is whether a pitch was intentionally thrown at a batter. Rule 8.02(d) does not apply in the absence of such intent. Whether the pitch was intentional or not is up to the umpire's judgement. In exercising their judgement, umpires have been instructed to be mindful that, given the skill level of most Major League pitchers, a pitch that is thrown at the head of a hitter more likely than not was thrown there intentionally. Umpires have been instructed to bear this presumption in mind in deciding whether a pitch was intentional.

Once Rule 8.02(d) is found to be applicable (because an umpire has determined in his judgement that a pitch was intentionally thrown at a batter) an umpire has two options: expel or warn the appropriate persons (the pitcher or the manager and the pitcher).

Rule 8.02(d) does not give the umpire the discretion to allow the opposing pitcher an opportunity to retaliate in kind before the warning or ejection. Nor does the Rule mandate, even in an instance where a pitcher has intentionally thrown at the head of a hitter, that the pitcher must be ejected.

Which of the two options is elected by the umpire under Rule 8.02(d) is at the discretion of the umpire, but the elected option will be based on all the surrounding circumstances. In assessing those circumstances, the umpire will take into account the note to Rule 8.02(d), which states that pitching at a batter's head is unsportsmanlike, highly dangerous and condemned within the sport.

The automatic fine for intentionally throwing at a batter is a minimum of $200. Each incident will be reviewed and further disciplinary action imposed on a case-by-case basis.

Rule 8.03: Pitcher Warm-Up

When a pitcher takes his position at the beginning of each inning, or when he relieves another pitcher, he shall be permitted to pitch not to exceed eight preparatory pitches to his catcher during which play shall be suspended. A league by its own action may limit the number of preparatory pitches to less than eight preparatory pitches. Such preparatory pitches shall not consume more than one minute of time. If a sudden emergency causes a pitcher to be summoned into the game without any opportunity to warm up, the umpire-in-chief shall allow him as many pitches as the umpire deems necessary.

Rule 9.00 - 9.05: The Umpire
9.01
  1. The league president shall appoint one or more umpires to officiate at each league championship game. The umpires shall be responsible for the conduct of the game in accordance with these official rules and for maintaining discipline and order on the playing field during the game.
  2. Each umpire is the representative of the league and of professional baseball, and is authorized and required to enforce all of these rules. Each umpire has authority to order a player, coach, manager or club officer or employee to do or refrain from doing anything which affects the administering of these rules, and to enforce the prescribed penalties.
  3. Each umpire has authority to rule on any point not specifically covered in these rules.
  4. Each umpire has authority to disqualify any player, coach, manager or substitute for objecting to decisions or for unsportsmanlike conduct or language, and to eject such disqualified person from the playing field. If an umpire disqualifies a player while a play is in progress, the disqualification shall not take effect until no further action is possible in that play.
  5. Each umpire has authority at his discretion to eject from the playing field (1) any person whose duties permit his presence on the field, such as ground crew members, ushers, photographers, newsmen, broadcasting crew members, etc., and (2) any spectator or other person not authorized to be on the playing field.
9.02
  1. Any umpire's decision which involves judgment, such as, but not limited to, whether a batted ball is fair or foul, whether a pitch is a strike or a ball, or whether a runner is safe or out, is final. No player, manager, coach or substitute shall object to any such judgment decisions.

    Rule 9.02(a) Comment: Players leaving their position in the field or on base, or managers or coaches leaving the bench or coaches box, to argue on BALLS AND STRIKES will not be permitted. They should be warned if they start for the plate to protest the call. If they continue, they will be ejected from the game.

  2. If there is reasonable doubt that any umpire's decision may be in conflict with the rules, the manager may appeal the decision and ask that a correct ruling be made. Such appeal shall be made only to the umpire who made the protested decision.
  3. If a decision is appealed, the umpire making the decision may ask another umpire for information before making a final decision. No umpire shall criticize, seek to reverse or interfere with another umpire's decision unless asked to do so by the umpire making it.

    Rule 9.02(c) Comment: A manager is permitted to ask the umpires for an explanation of the play and how the umpires have exercised their discretion to eliminate the results and consequences of the earlier call that the umpires are reversing. Once the umpires explain the result of the play, however, no one is permitted to argue that the umpires should have exercised their discretion in a different manner.
    The manager or the catcher may request the plate umpire to ask his partner for help on a half swing when the plate umpire calls the pitch a ball, but not when the pitch is called a strike. The manager may not complain that the umpire made an improper call, but only that he did not ask his partner for help. Field umpires must be alerted to the request from the plate umpire and quickly respond. Managers may not protest the call of a ball or strike on the pretense they are asking for information about a half swing.
    Appeals on a half swing may be made only on the call of ball and when asked to appeal, the home plate umpire must refer to a base umpire for his judgment on the half swing. Should the base umpire call the pitch a strike, the strike call shall prevail.
    Baserunners must be alert to the possibility that the base umpire on appeal from the plate umpire may reverse the call of a ball to the call of a strike, in which event the runner is in jeopardy of being out by the catcher's throw. Also, a catcher must be alert in a base stealing situation if a ball call is reversedto a strike by the base umpire upon appeal from the plate umpire.
    The ball is in play on appeal on a half swing.
    On a half swing, if the manager comes out to argue with first or third base umpire and if after being warned he persists in arguing, he can be ejected as he is now arguing over a called ball or strike.

  4. No umpire may be replaced during a game unless he is injured or becomes ill.
9.03
  1. If there is only one umpire, he shall have complete jurisdiction in administering the rules. He may take any position on the playing field which will enable him to discharge his duties (usually) behind the catcher, but sometimes behind the pitcher if there are runners).
  2. If there are two or more umpires, one shall be designated umpire-in-chief and the others field umpires.
9.04
  1. The umpire-in-chief shall stand behind the catcher. (He usually is called the plate umpire.) His duties shall be to:
    1. Take full charge of, and be responsible for, the proper conduct of the game;
    2. Call and count balls and strike;
    3. Call and declare fair balls and fouls except those commonly called by field umpires;
    4. Make all decisions on the batter;
    5. Make all decisions except those commonly reserved for the field umpires;
    6. Decide when a game shall be forfeited;
    7. If a time limit has been set, announce the fact and the time set before the game starts;
    8. Inform the official scorer of the official batting order, and any changes in the lineups and batting order, on request;
    9. Announce any special ground rules, at his discretion.
  2. A field umpire may take any position on the playing field he thinks best suited to make impending decisions on the bases. His duties shall be to:
    1. Make all decisions on the bases except those specifically reserved to the umpire in chief;
    2. Take concurrent jurisdiction with the umpire in chief in calling "Time," balks, illegal pitches, or defacement or discoloration of the ball by any player.
    3. Aid the umpire-in-chief in every manner in enforcing the rules, and excepting the power to forfeit the game, shall have equal authority with the umpire-in-chief in administering and enforcing the rules and maintaining discipline.
  3. If different decisions should be made on one play by different umpires, the Crew Chief shall call all the umpires into consultation, with no manager or player present. After consultation, the Crew Chief shall determine which decision shall prevail, based on which umpire was in best position and which decision was most likely correct. Play shall proceed as if only the final decision had been made.
9.05
  1. The umpire shall report to the Office of the Commissioner within 12 hours after the end of a game all violations of rules and other incidents worthy of comment, including the disqualification of any trainer, manager, coach or player, and the reasons therefore.
  2. When any trainer, manager, coach or player is disqualified for a flagrant offense such as the use of obscene or indecent language, or an assault upon an umpire, trainer, manager, coach or player, the umpire shall forward full particulars to the Office of the Commissioner within four hours after the end of the game.
  3. After receiving the umpire's report that a trainer, manager, coach or player has been disqualified, the Office of the Commissioner shall impose such penalty as it deems justified, and shall notify the person penalized and the manager of the club of which the penalized person is a member. If the penalty includes a fine, the penalized person shall pay the amount of the fine to the Office of the Commissioner within five days after receiving notice of the fine. Failure to pay such fine within five days shall result in the offender being debarred from participation in any game and from sitting on the players' bench during any game, until the fine is paid.
Weather Conditions
3.10
  1. The home team shall be the sole judge as to whether a game shall not be started because of unsuitable weather conditions or the unfit condition of the playing field, except for the second game of a doubleheader. EXCEPTION: Any league may permanently authorize its president to suspend the application of this rule as to that league during the closing weeks of its championship season in order to assure that the championship is decided each year on its merits. When the postponement of, and possible failure to play, a game in the final series of a championship season between any two teams might affect the final standing of any club in the league, the president, on appeal from any league club, may assume the authority granted the home team by this rule.
  2. The umpire-in-chief of the first game shall be the sole judge as to whether the second game of a doubleheader shall not be started because of unsuitable weather conditions or the unfit condition of the playing field.
4.01
  1. The Crew Chief shall be the sole judge as to whether and when play shall be suspended during a game because of unsuitable weather conditions or the unfit condition of the playing field; as to whether and when the play shall be resumed after such suspension; and as to whether and when a game shall be terminated after such suspension. He shall not call the game until at least 30 minutes after he has suspended play. He may continue the suspension as long as he believes there is any chance to resume play.

    Rule 4.01 Comment: ... The umpire-in-chief shall at all times try to complete a game. His authority to resume play following one or more suspensions of as much as 30 minutes each shall be absolute and he shall terminate a game only when there appears to be no possibility of completing it. ...

Rosin Bags

In January 1926, the major league rules committee approved the following regulation for the use of rosin bags. The rule was first approved only by the National League, but the American League followed suit a couple months later.

"Under the supervision and control of the umpire, the pitcher may use to dry his hands a small, finely meshed sealed bag containing powdered rosin, furnished by the League."

The current rule states the following:

"All umpires shall carry with them one official rosin bag. The umpire-in-chief is responsible for placing the rosin bag on the ground back of the pitcher's plate. If at any time the ball hits the rosin bag it is in play. In the case of rain or a wet field, the umpire may instruct the pitcher to carry the rosin bag in his hip pocket. A pitcher may use the rosin bag for the purpose of applying rosin to his bare hand or hands. Neither the pitcher nor any other player shall dust the ball with the rosin bag; neither shall the pitcher nor any other player be permitted to apply rosin from the bag to his glove or dust any part of his uniform with the rosin bag."

Protective Elbow Pads

The Office of the Commissioner of Baseball and the Major League Baseball Players Association agreed to standardize the elbow protective equipment a player may use for all major league games, including spring training games. The following regulations apply to elbow protection:

  • No player is permitted to wear an elbow protection pad that exceeds 10 inches in length, as measured when the pad is lying flat.
  • A nylon pad shall surround the shell of any elbow protection equipment.
  • A manufacturer's logo on the protection pad may appear in one location and shall not exceed one square inch.
  • No player may wear a non-standard elbow protection pad, or any pad designed to protect the upper or lower arm, unless the player has an existing elbow or other arm injury and the Club had obtained the prior approval of the Commissioner's Office to wear that particular non-standard equipment. To obtain such prior approval, the Club will be requested to provide the following:
  • A letter identifying the player and describing the nature of the injury and describing the proposed elbow protection pad;
  • A physician's report diagnosing the injury; and
  • A physician's estimate of length of time the protective pad will be necessary.
  • If, during the course of a major league game, a Club has a complaint regarding the use of protective elbow pads, that Club should alert the home plate umpire working that night's game. Following the game, the Crew Chief will file an Umpire's Report regarding the complaint to the Commissioner's Office, which will immediately begin an investigation. The Club's General Manager should also report the violation to Frank Robinson, Vice President for On-Field Operations at the Office of the Commissioner. A Club will be subject to discipline if any of its players are found to have used a non-standard elbow pad without the prior approval of the Office of the Commissioner. The umpires will not be enforcing these guidelines on the playing field, either before or during a game. If a Club has a complaint about a violation of this policy, it must follow the complaint procedures described above and should not expect enforcement by the umpires on the spot.