Professional Softball Rules & Format

The Athletes Unlimited Softball League (AUSL) will host its inaugural regular season in the summer of 2025. The women’s professional softball league will feature four teams in its first season, touring to 6-8 different cities across the United States.

Learn more about the rules of professional softball.

The Teams

Each team features 15 players on the roster. 

A lineup is made up of nine to 10 players. If a pitcher is batting, the team will have nine players in a lineup. If a pitcher does not bat, the team will have ten players on a lineup, with the tenth batter – the designated player (DP) – remaining in the dugout while their team plays defense. The remaining five to six players may enter a game off the bench as substitutes.

7 Innings

A softball game is composed of seven innings. A game may be extended due to a tie score or shortened if the home team leads following the top of the 7th inning. 

The visiting team begins the game on offense (at bat), and its objective is to have its batters become base runners and advance, touching all bases without being put out. Each time this is done, a run is scored. 

The home team starts the game on defense (in the field), and its objective is to prevent offensive players from becoming base runners and advancing around the bases.

When three offensive players are legally put out, a half-inning has been played, and the teams change from offense to defense and defense to offense, respectively.

Fielding Positions

Softball features the following fielding positions:

• Infield – Comprising the first baseman, second baseman, shortstop (between second and third base), and third baseman
• Outfield – Comprising the right fielder (outfield position between first and second base), center fielder (behind second base), and left fielder (between second and third)
• Pitcher – In the circle in the middle of the infield
• Catcher – Behind home plate

The tandem of the pitcher and catch is also known as “the battery.”

Scoring

The object of each team is to score more runs than its opponent. The winner of the game will be the team that has scored a greater number of runs at the end of a regulation-length game. A run is scored each time a runner safely touches first, second, third, and home plate before the third out of an inning. 

A player can score a run with a single swing by hitting a pitch over the outfield fence – known as a “home run” – and round the bases. Runs can also be scored when a team strings multiple hits and walks together in an inning.

A player can get on base by getting a “hit”, which is hitting a pitch that lands safely in the field of play and running 60 feet to first base before an out is made. A batter can also safely reach on an extra-base hit by hitting a “double” (two bases) or “triple” (three bases). Though rare, a batter can also round all bases by hitting an “inside-the-park home run.”

A batter can also be awarded first base if they are hit by a pitch, the pitcher throws four balls outside the strike zone (a “walk”), or if they are intentionally walked. 

The AUSL All-Star Cup has a unique scoring system in which players earn individual points for different actions during a game. Learn more about the AUSL All-Star Cup format.

Securing an Out

An out is made if a batter hits a ball that is caught on the fly by the opponent, if a ground ball is fielded and thrown to the first baseman before the batter reaches the base, or if a batter is tagged out while in between bases. 

A batter will also be called out during a plate appearance if they see three strikes before putting the ball in play or being walked.

Baserunning

While on the base path, a player can “steal” another base without the ball being hit. The runner may not leave the base until after the pitcher releases the ball. If the runner is tagged with the ball before reaching the base, they are “caught stealing” and out.

A “double play” occurs when two outs are made on the same play. This commonly occurs when an out is made at second base and the fielder throws to first base before the runner reaches. 

On a fly ball, a runner cannot leave the base until after the ball is caught by the fielder, known as “tagging up.” If a base runner leaves too early, they must go back and touch the base. If the ball gets to the base before they return, they are out.

Pitching

The pitcher tosses the ball underhanded toward the plate in professional softball, aiming for the strike zone. The strike zone generally covers the width of home plate and the area between a batter’s knees and chest – often near their jersey letters. A “strike” is called when a pitch crosses the strike zone and the batter does not swing or when the batter swings at a pitch and misses.

If a batter makes contact with a pitch but hits it into foul territory, it is known as a “foul ball.” A foul ball is a strike if it occurs within the first two strikes of an at-bat. A batter can not strike out on a foul ball.

A pitch out of the strike zone that the batter does not swing at is a “ball.” A batter will be awarded first base after four balls in a plate appearance. A pitcher does not need to throw a pitch if intentionally walking a batter. This is instead signaled to the home plate umpire and the batter is immediately awarded first base.

A pitcher’s job is to allow as few runs as possible throughout an outing. A pitcher may pitch the entire game, known as a “complete game,” or be replaced by a relief pitcher. If a pitcher pitches a complete game allowing no hits, it is called a “no-hitter.” If they allow no baserunners, it is known as a ”perfect game.”

A “combined no-hitter” is when a starting pitcher and relief pitcher(s) combine to allow no hits.