ASA Slow-pitch softball rules will govern all play with the following modifications.

Personal Conduct

  1. Players: Under no circumstances may players harass, threaten, intimidate, or physically engage in confrontation with umpires and/or field supervisors. Players who violate this policy will face ejection from the game, league, and all other intramural sports as determined by the Intramural Sports Coordinator.
  2. Coaches and Spectators: Coaches and spectators will be held to the same standard as intramural competitors. Teams with unruly coaches and spectators risk forfeiture and other penalties as determined by the Intramural Sports Coordinator.
  3. Ejections: Any player, coach, or spectator ejected from a competition will automatically be suspended from participating in the next scheduled competition. That individual will remain ineligible until meeting with the Intramural Sports Coordinator to determine additional suspension and/or penalty.
  4. Alcohol: Alcoholic beverages are prohibited in all University recreational areas. Violation of this MSU policy will be forwarded to the MSU Police Department.

The Game

  1. Ten players make up a full team; eight players must be present to start the game.
  2. The 3-ball, 2-strike count will be used in all games; each batter will start an at bat with a 1-1 count.
  3. Each game will consist of six complete innings unless the time limit has been reached or the mercy rule is in effect.
    1. Time limit: A time limit of 50 minutes is set to complete each game. No new inning can begin once the time limit has been reached.
    2. Mercy rule: A mercy rule of 15 runs is in effect after three full innings of play. Should both teams agree, the game may be continued “just for fun” until the time limit is reached. The final score will be recorded as it was when the mercy rule went into effect.


  1. Gym shoes, soft-soled shoes, or molded plastic cleats may be worn during competition. Metal spikes are strictly prohibited. All players must wear close toed shoes.
  2. Regulation softballs will be provided by the Rec Sports department. Each team should bring gloves and at least one bat for use. The bat must be an approved USSSA or ASA slowpitch softball bat. Baseball and fastpitch softball bats are prohibited.
  3. Batting helmets and catcher’s equipment are recommended. These items must be supplied by the individual if they choose to wear them. The Rec Sports department is not responsible for any injury that occurs during competition as the result of not wearing a batting helmet or catcher’s equipment.
  4. Jewelry should not be worn during competition. The Rec Sports department is not responsible for any breakage, loss, or injury that occurs as the result of wearing jewelry during competition.


  1. The pitcher must present the ball in front of their body.
  2. The pitcher may hold the ball in any manner before delivery.
  3. The pitcher may only deliver the pitch with a definite underhand motion.
  4. The pitcher must face home plate before and during delivery of the pitch.
  5. The ball must be pitched at a slow speed.
  6. The pitched ball must arc at least three feet after leaving the pitcher’s hand and before it passes any part of home plate.
  7. The pitched ball shall not rise higher than twelve feet above the ground.
    1. The speed and height of the pitched ball are left entirely to the judgment of the umpire. Any doubtful pitch should be ruled as an unfairly delivered pitch.
    2. The pitcher must engage the pitching rubber with one or two feet planted firmly on the ground.
    3. The pitcher must come to a complete set position prior to beginning their wind up.
    *three warm up pitches will be granted between each inning. The umpire will make the final decision as to the number of warm up pitches allowed.


  1. The strike zone is defined as any ball that strikes the back half of home plate (pointed portion) or the mat that sits behind home plate.
  2. Only three foul balls are permitted in each at bat. At any time throughout their plate appearance, if the batter hits three fouls balls (including dropped foul tips) they will be declared out. The ball is determined dead and the runners may not advance.
  3. Bunting and/or chopping the ball downward is prohibited. If this occurs, the batter is declared out, the ball is dead, and runners may not advance.
  4. Throwing of the bat in any manner is prohibited. On the first occurrence, a warning will be issued by the umpire. On the second occurrence, the batter will be declared out. On the third occurrence, the player will be ejected from the game.
  5. Only one home run will be permitted per team per inning. If more than one home run is hit, each subsequent home run thereafter will be declared an out and base runners will be returned to the base in which they occupied before the at bat.

Fielding and Baserunning

  1. Ground rules for each field will be explained by the head umpire or field supervisor prior to the start of each game.
  2. The catcher should position themselves at a safe distance behind home plate as to not get hit with the bat during the follow through of the batter’s swing. The umpire reserves the right to ensure safety by asking the catcher to move farther away from home plate.
  3. Baserunners may not attempt to steal a base. Baserunners may leave the base at their own risk when the ball crosses home plate and must return to the base after each pitch if the ball is not put into play.
  4. Baserunners may not interfere with defensive players that are involved with making a play on the ball, regardless of whether the defensive player is located in the base line.
  5. Defensive players who are not involved in making a play on the ball may not obstruct baserunners that are legally running from base to base regardless of whether the runner appears to be out of the base line.
  6. Baserunners may not make contact with defensive players with significant force in an attempt to dislodge the ball. If this occurs, the baserunner will be declared out and will be ejected from the game immediately.
  7. Baserunners may slide or try to avoid contact on plays involving defensive players.
  8. Baserunners will be declared out when struck by a batted, fair ball, unless the ball has passed the first defender (except the pitcher) and no other defender stands to make a play on the ball.


  1. Standard substitution: teams must list the players that will bat and play defense on the score sheet. The starting players may be taken out of the game one time and may re-enter the game one time. Teams can make changes during innings and between innings if they choose to do so. Pinch hitters and runners are allowed.
  2. Unlimited substitution: teams must list all players that will bat and play defense on the score sheet. This number may exceed 10 players. However, only 10 players may play defense at a time. Every player listed on the score sheet must bat. Players may go in and come out of the game as many times as they choose, but, teams can only make defensive changes between innings. Pinch hitters and runners are not allowed.
  3. Teams must announce their substitution method to the umpire prior to the start of the game. Each team can choose either the standard substitution or unlimited substitution method. Once the choice has been made, a team must abide by the respective rules.

CoRec Modifications

  1. A standard team consists of five males and five females with a minimum of four males and four females.
  2. The batting order must alternate male-female or female-male throughout the entire game. If a team has an odd number of players, the batting order must still alternate male-female or female-male.
  3. If a male earns a base on balls in his plate appearance, the next female batter has the option to take an automatic base on balls. If she elects to take the base on balls, she can advance to first base. If she elects to bat, she must bat and will adhere to the result of her plate appearance.