Rule 9.01
The official scorer
The official scorer is appointed by the league and makes every call that is a matter of scoring judgment: whether a play was a hit or an error, or whether it was a passed ball or a wild pitch. The scorer cannot contradict the umpires, who rule on what happens on the field. There is a limited time after the game to review any decision.
Rule 9.02
The official score report
Sets out what the scorer must record for each player: at-bats, runs, hits, runs batted in, walks, strikeouts, putouts, assists and errors, and for pitchers, innings pitched, hits, runs and earned runs. It also explains when a plate appearance does not count as an at-bat: a sacrifice, a walk, a hit by pitch, and interference or obstruction.
Rule 9.03
Special cases in the report
Explains how to score cases that fall outside the usual: a batter who bats out of turn, substitutes, suspended games and forfeited games. It includes the box score proof: a check that confirms the game's scoring adds up.
Rule 9.04
Runs batted in
The batter is credited with a run batted in when a run scores because of the batter's hit, sacrifice, infield out or fielder's choice, or on a walk or hit by pitch with the bases loaded. No RBI is credited when the batter grounds into a double play or, in the scorer's judgment, when the run scores because of an error.
Rule 9.05
When it's a hit
It's a hit when the batter reaches first base safely on a fair ball, without the help of an error or a fielder's choice. It's not a hit if a runner is forced out on the play, or if the fielder could have made the out with ordinary effort.
Rule 9.06
How many bases a hit is worth
Decides whether the hit is a single, double, triple or home run based on the bases the batter reaches on the hit alone, without errors or plays on other runners. Special case: on a game-ending hit, only the bases needed for the winning run to score are counted, except for a home run hit out of the park.
Rule 9.07
Stolen bases and caught stealing
A stolen base is credited when a runner advances without the help of a hit, an out, an error, a fielder's choice, a wild pitch, a passed ball or a balk. If the defense makes no attempt to stop the runner, it is scored as defensive indifference, not a stolen base.
Rule 9.08
Sacrifices
Two cases: the sacrifice bunt, which advances runners with fewer than two outs, and the sacrifice fly, which lets a runner score from third with fewer than two outs. Neither one counts as an at-bat.
Rule 9.09
Putouts
The putout is credited to the fielder who catches the batted ball, tags the runner or touches the base on a force play. On a strikeout, the putout goes to the catcher. Some automatic putouts also go to the catcher, such as the one for a batter who bats out of turn.
Rule 9.10
Assists
An assist is credited to each fielder who throws or deflects the ball on a play that results in an out, or that would have resulted in an out if not for a later error.
Rule 9.11
Double and triple plays
Each fielder who takes part in a double or triple play is credited with participating in it, as long as there is no error between the outs.
Rule 9.12
Errors
It's an error when a fielder fails to make a play that should have been made with ordinary effort, and that prolongs the batter's time at bat, keeps a runner alive or lets a runner advance. Mental mistakes and misjudgments are not scored as errors. A wild throw that lets a runner advance also counts.
Rule 9.13
Wild pitch and passed ball
A wild pitch is a pitch so far off target that the catcher can't control it with ordinary effort, and a runner advances: it's the pitcher's fault. A passed ball is a pitch the catcher should have handled and didn't: it's the catcher's fault.
Rule 9.14
Base on balls
A base on balls is awarded when the batter receives four balls. It includes the intentional walk, which today can be granted without throwing a pitch, at the manager's signal.
Rule 9.15
Strikeouts
A strikeout is scored when the batter gets three strikes, including a bunt foul with two strikes. If the third strike isn't caught and the batter reaches first, the pitcher is still credited with the strikeout.
Rule 9.16
Earned runs
A run is earned when the pitcher is responsible for it. To decide, the scorer reconstructs the inning as if there had been no errors or passed balls. When a reliever comes in, the runners left on base by the previous pitcher remain that pitcher's responsibility.
Rule 9.17
Winning and losing pitcher
The starting pitcher gets the win if he pitched at least five complete innings and his team took a lead it never gave up. If he doesn't qualify, the scorer picks the reliever who most deserved it. The loss goes to the pitcher responsible for the run that gave the opponent the lead for good.
Rule 9.18
Shutouts
A shutout is credited to the pitcher who allows no runs in the entire game, or to a reliever who comes in with no outs, before any run has scored, and finishes the game without allowing a run.
Rule 9.19
Saves
A save is credited to the pitcher who finishes a game his team won without being the winning pitcher, pitches at least one-third of an inning and meets one condition: he enters with a lead of three runs or fewer and pitches a full inning; or he enters with the tying run on base, at bat or on deck; or he pitches at least three innings.
Rule 9.20
Statistics
The league statistician keeps the official records of every player based on the scorer's reports. They are the basis for the season's cumulative statistics.
Rule 9.21
How percentages are calculated
Sets out the official formulas:
- Batting average (AVG)
- Hits ÷ At-bats
- Slugging percentage (SLG)
- Total bases ÷ At-bats
- On-base percentage (OBP)
- (Hits + Walks + Hit by pitch) ÷ (At-bats + Walks + Hit by pitch + Sacrifice flies)
- Earned run average (ERA)
- Earned runs × 9 ÷ Innings pitched
- Fielding percentage
- (Putouts + Assists) ÷ (Putouts + Assists + Errors)
Rule 9.22
Minimums for titles
Sets the minimum a player must play to qualify for a title. For the batting title, 3.1 plate appearances for each game the team plays. For the ERA title, one inning pitched for each game the team plays.
Rule 9.23
Streaks
Explains when a hitting streak continues or ends. A consecutive-game hitting streak isn't broken if, in that game, the batter only drew walks, was hit by pitches, reached on interference or laid down a sacrifice bunt. A sacrifice fly with no hit does end it.