Baseball · MLB
Based on the supplied MLB Official Baseball Rules 2025. Separate operational regulations and later amendments are not inferred.
Rules
The game and scoring
Teams, innings, outs and when a run counts.
Field and equipment
The diamond, bases, mound, bats and protective equipment.
Lineups and substitutions
A fixed batting order, replacements and limits on returning.
Defensive positioning
Fair territory and the MLB restrictions on infield shifts.
Balls, strikes and batting
The strike zone, walks, foul balls and batting obligations.
Fair balls, foul balls and catches
Where the ball is judged and what makes a legal catch.
Reaching first base
Hits, walks, hit batters and the uncaught third strike.
Running the bases and making outs
Force plays, tags, overrunning first and runner responsibilities.
Base awards and dead balls
Home runs, balls out of play and why awards are not always identical.
Pitching and balks
Legal delivery, pickoff throws and the protection against illegal deception.
Pitching changes and mound visits
The minimum batters requirement and MLB’s visit allowance.
The designated hitter
Batting for the pitcher and the starting pitcher’s dual role.
Appeals and batting out of turn
Missed bases, leaving early and the deadline for a batting-order appeal.
The infield fly
Preventing an easy fly ball from becoming an unfair double play.
Interference and obstruction
Distinguishing an offense hindering a play from a defense blocking a runner.
Slides and home-plate collisions
Legal attempts at a base and protection against avoidable collisions.
Extra innings
The regular-season runner on second and the postseason exception.
Weather and ending games
Regulation games, suspensions, resumptions and forfeits.
Umpires and conduct
Authority, rule questions, discipline and the limits of this source.
Official scoring and statistics
Hits, errors, earned runs and the distinction between scoring and umpiring.
Compare the supplied editions, including event-specific exceptions.