Equipment
The baseball is 9-9 ¼ inches in circumference and 5-5 ¼ ounces in weight. It is made of wool and twine wrapped around a rubber-covered cork center, then covered with two strips of white leather, stitched together. The bat must be no more than 42 inches long and 2 ¾ inches thick at its greatest diameter. It must be made of one solid piece of wood, generally circular in cross section.
The catcher wears a mask, chest protector, shin guards, and a leather glove, or mitt, of any size or weight. The first baseman may use a leather glove no more than 12 inches long and no more than 8 inches wide, with leather or lacing between the thumb and palm. Other fielders may wear leather gloves of the same maximum dimensions, but they must be finger-type gloves, not trapping mitts of the type used by the first baseman.
Playing Field
The baseball "diamond" is actually a square, 90 feet on a side. Home plate is a five-sided slab of white rubber, set flush with the ground; its pointed angle fits into one corner of the diamond. The plate is 17 inches wide on its longest side, which is parallel to the pitcher's rubber. At each of the other three corners of the diamond is a base, a stuffed canvas bag 15 inches square.
Base paths are marked by chalked lines. The lines between home plate and first base and between home plate and third base are extended beyond the bases to the outfield fences, forming a large V which is "fair territory."
The pitcher's mound is a circular area of dirt, 18 feet in diameter, built up to no more than 10 inches at its highest point. At its center is the pitcher's plate, or rubber, a white rubber slab set flush with the ground. It is 2 feet long and 6 inches wide. The front edge of the rubber is 60 feet, 6 inches from the farthest portion of home plate.
Defensive Positions
There are nine defensive players in each starting lineup. Two of them, the pitcher and catcher, form the "battery"; they are the only players who must take a definite spot on the field. The pitcher, before beginning the delivery, must have one foot on the rubber and, once the pitching motion is begun, the foot must remain there until the ball is released. The catcher must stay in the catcher's box, a rectangle 8 feet long and 43 inches wide, from the moment the pitcher's motion is begun until the ball leaves the pitcher's hand.
Other defensive players may take up any positions they wish, but they must be in fair territory when the pitcher delivers the ball.
Progress of Play
The game begins with the visiting team at bat and the home team in the field. After three outs, the visiting team is retired and the home team comes to bat. Once both teams have had a turn at bat, an inning is completed. A regulation game consists of nine innings.
The object of the game is to score runs by advancing runners around the bases, in sequence; each runner who reaches home plate scores a run. The team with the most runs at the end of nine innings wins the game. If the score is tied after nine innings have been played, the game continues until, at the end of an inning, one team is ahead. If, at the end of eight and a half innings, the home team is ahead, the game is over. If, at any point after eight and a half innings, the home team goes ahead, the game ends immediately.
The Batter
The batter must stand in a chalk-lined box, 4 feet wide by 6 feet long, to the left or right of home plate. Once this position is taken, and the ball is in possession of the pitcher while on the rubber, the batter can't leave the box without asking the umpire to call time out. Time out cannot be called once the pitcher's motion has begun.
The batter may swing or not at any delivery by the pitcher. If the batter swings and fails to hit the ball, it is a strike. If the batter hits the ball into foul territory, it is also a strike, unless the count is already two strikes. If, with a count of two strikes, the batter bunts the ball foul, or foul tips the ball directly into the catcher's mitt, it is a third strike.
It is also a strike if the batter doesn't swing at a pitch that passes through the strike zone.
The top of the strike zone is the midpoint between the top of the shoulders and the top of the uniform pants; the bottom is a line through the hollow beneath the knee cap. If the pitch does not pass through the strike zone and the batter doesn't swing at it, it is a "ball."
After three strikes, the batter is out. (However, the catcher must catch the third strike to retire the batter. If the catcher doesn't catch it, the batter can attempt to go to first base, and the catcher must then tag or throw out the batter. This exception doesn't apply if first base is occupied, and there are fewer than two outs.) After four balls, the batter is entitled to go to first base.
The batter is also out if:
- The batted ball, fair or foul, is caught by a fielder before it touches the ground or any other object.
- The third strike hits the batter.
- The batted fair ball hits the batter before it touches a fielder.
- The batter hits the ball in fair territory and it is held by a fielder on first base before the batter reaches the base, or if the batter is touched by the ball, in possession of a fielder, before reaching the base.
- The batter deliberately drops, throws, or otherwise uses the bat to touch a fair ball.
The batter is awarded first base if:
- The batter is hit by a pitch, unless the pitch passes through the strike zone or the batter swings at it.
- The batter is interfered with, by the catcher or any other fielder, when swinging or when attempting to run to first base.
- The batted fair ball hits an umpire before it touches or passes a fielder other than the pitcher.
- The batted fair ball hits a runner before touching or passing a fielder other than the pitcher. (The runner is out, and no other runner may advance, unless forced to advance.)
- If the batter hits a fair ball over the fence, it is a home run, and the batter is entitled to advance around the bases. (Each base must be touched in turn.) If the ball bounces over the fence, the batter is normally awarded two bases (a ground-rule double), and each runner also advances two bases.
The Runner
The basic rules involving runners are:
Once a runner has gained a base, that runner alone is entitled to the base, unless required to advance.
However, the batter who hits a fair ball becomes a runner and is entitled to first base, and the runner originally on first base must advance to second. If there is also a runner on second, there must be a corresponding advance to third; if there is also a runner on third, that runner must advance to home plate.
A runner is out if tagged by a fielder with the live ball while the runner is off base.
If a runner is required to advance, the runner is awarded the next base when the batter is awarded first base.
A runner who is required to advance doesn't have to be tagged out; the runner is out when the base is tagged before the runner reaches it. However, if the runner following the first one is put out, the force is removed. (For example, there is a runner on first base. The ball is hit to the pitcher, who throws the batter out at first base. The force is now removed and the runner who was on first base must be tagged out; that runner may now return to first base.)
To score, a runner must touch the bases in their proper order.
A runner starting from a given base cannot advance on a caught fly ball unless he or she first retouches that base after the catch.
A runner, when required to retouch, must retouch all bases in reverse order.
If two runners are on the same base, the first runner to reach it is entitled to it, unless required to advance. The second runner must return to the previous base before being tagged, or before the previous base is tagged.
If the batter hits a home run, all runners are entitled to advance around the bases to home plate, but they must touch each base in the proper order.
The Runner's Advancement
The runner is entitled to advance:
- One base, if a fielder, after catching a fly ball, falls into a bench or a stand.
- One base if, when the runner is attempting to steal, the batter is interfered with.
- Two bases if a fielder deliberately touches a thrown ball with glove, cap, mask, or any other part of the uniform while such an item is not in its usual place. (If, for example, a fielder attempts to use cap or mask to catch the ball, or if the fielder throws a glove at the ball.)
- Two bases if a thrown ball goes into the stands or a bench, or through a fence or screen, or if it is caught in the meshes of a screen. (However, the runner gets only one base if this occurs on a pitch, or on a throw by the pitcher in an attempt to pick a runner off base.)
- Three bases, if a fielder deliberately touches a batted ball with glove, cap, mask, or another part of the uniform while it is not in its usual place.
Interference and Obstruction
Interference is usually the act of a batter or runner that makes it difficult for a fielder to make a play. The player interfering is usually called out. Obstruction is the act of a defensive player that impedes a runner's attempt to advance. The runner is awarded one or more bases.
It is interference when:
- A runner deliberately interferes with a thrown ball, or with a fielder trying to make a play on a batted ball, (If, in the umpire's judgment, the interference prevented a double play, both runners are called out.)
- A runner is hit by a batted ball before it passes or is touched by a fielder. (The batter is awarded first base.)
- A runner deliberately kicks a batted ball, even after it has passed or been touched by a fielder.
- A coach physically assists a runner by touching the runner.
Obstruction plays arise rarely; it is important to note that the fielder who is making a play has the right of way, and it is up to the runner to avoid the fielder. However, if a fielder who is not involved in the play stands in a runner's path, it is obstruction. If a play is being made, or is about to be made, on the obstructed runner, the runner is awarded at least one base. If no play is being made on the runner, play continues; when it is complete, the umpire can impose penalties to nullify the obstruction, by awarding as many additional bases to the runner as the umpire feels the obstruction cost the runner.
Appeal Plays
On certain plays, it is up to the fielding team to point out a violation of rules to an umpire before the umpire can take any action. If a runner misses a base, for example, the umpire cannot simply call the runner out. Before the next pitch to the batter, or the next play (such as an attempted pick-off), a member of the fielding team must throw the ball to that base, tag the base, and appeal to the umpire, who then rules on whether or not the runner did miss the base.
It is also an appeal play if the runner leaves base before a fly ball is caught; if the runner misses home plate while sliding in an attempt to score; or if the runner overruns or overslides first base and doesn't return immediately.
Dead Balls
Normally, a runner may attempt to advance at his own peril whenever the ball is alive (in play). If the ball is dead, however, runners may not advance, nor may they be put out. The ball is dead when:
- The batter is interfered with.
- The ball strikes an umpire or a runner before it is touched by or passes a fielder.
- A pitched ball hits the batter.
- A runner or the batter commits interference.
- The ball goes out of the field or into the crowd or a bench.
- The ball is hit into foul territory, unless it is caught on the fly.
- An umpire has called time out.
- The plate umpire interferes with the catcher's attempt to throw.
- The pitcher commits a balk.
The ball becomes live again when the pitcher has the ball on the rubber and the plate umpire calls "play."
The Pitcher
Once the pitcher has reached the mound to begin an inning or to replace another pitcher, eight practice pitches are allowed. (However, if the previous pitcher was forced out of the game by illness or injury, the replacement is entitled to as many pitches as may be needed for warming up.)
The pitcher is allowed to pitch from either of two positions. In either case, the pivot foot (the right foot for a right-handed pitcher) must be in contact with the pitcher's plate from the moment the pitcher begins pitching motion until the moment the ball is released.
In the windup position, usually used when the bases are not occupied, the pitcher approximately faces the batter. Once the pitching motion begins, the pitcher may take one step backward and one step forward with the free foot; aside from that, the pitcher must not raise either foot from the ground.
In the set position, usually used when the pitcher wants to hold runners close to their bases, the pitcher begins with the free foot in front of the rubber, and the ball is held in both hands at the waist or chest. From that position, the pitcher may "stretch"--bring the ball up over the head and back down-but must return to the set position, stopping the pitching motion, before delivering the ball. From the set position, the pitcher may also throw to a base or step backward, off the rubber, with the pivot foot.
If the pitcher makes an illegal pitch with the bases unoccupied, it is called a ball, unless the batter reaches base on the ensuing play.
The pitcher may not bring the pitching hand into contact with the mouth while anywhere on the mound. Each violation results in a called ball. The pitcher may not apply any foreign substance to the ball; spit on the ball, on the pitching hand, or on the glove; or deface the ball in any way. For such violations the pitcher can be ejected from the game.
If, in the umpire's judgment, the pitcher intentionally throws at a batter, the pitcher is warned; if there is a repetition of such an act at any time during the game, the pitcher is ejected.
Balks
With runners on base, it is a balk if the pitcher:
- Makes any motion associated with the delivery but does not pitch.
- Fakes a throw to first base while on the rubber.
- Throws to a base without stepping directly toward that base, while on the rubber.
- Makes an illegal pitch.
- Makes any motion associated with the normal pitching motion, while not on the rubber.
- Fakes a pitch when not in possession of the ball.
- From the set position, removes one hand from the ball without pitching or throwing it.
- Drops the ball while on the rubber.
- Pitches when the catcher is not in the catcher's box.
- Throws from the set position without having come to a stop.
On a balk, each base runner is awarded one base. However, if the batter reaches base on the play that results from the balk, and each runner advances one base or more, the play stands.
Infield Fly Rule
The infield fly rule applies only with fewer than two out and runners on first and second bases or on first, second, and third. If the ball is hit into the air and, in the judgment of the umpire, it can be caught by an infielder with ordinary effort, it is an infield fly. The batter is automatically out.
The intent of the rule is to prevent an infielder from deliberately dropping the ball, or letting it drop, in order to get a double play by forcing out two runners. A similar rule states that the batter is automatically out if a fielder intentionally drops a fly ball or a line drive with a runner on first base.
Fair or Foul
When the ball remains in the infield, it is fair only if it comes to rest, or is touched by a fielder in fair territory. If it is hit to the outfield, it is a fair ball if it touched fair territory in the infield and was on, or over, fair territory when it left the infield; or if it lands, on the fly, in fair territory. Thus a ball that bounces directly over third base, but lands in foul territory in the outfield, is a fair ball. But if it is hit on the fly over third base, and lands in foul territory, it is a foul ball.
If an infield fly lands in foul territory, or is not caught and bounces into foul territory while still in the infield, it is a foul ball and the infield fly rule no longer applies.
Substitutions
A substitute may enter the game at any time the ball is dead. The manager must announce the substitution to the umpire. Once the manager has announced it, the substitution is made. Once replaced by a substitute, a player may not -return to the game.
A pinch hitter entering the game may be removed immediately for another pinch hitter; but the first pinch hitter has been in the game, and may not re-enter.
If a substitute pitcher enters the game, the newcomer must finish pitching to the batter then at the plate, or to any pinch hitter for that batter. If the inning ends before that batter has completed his time at bat (for example, if a runner is caught stealing for the third out), that pitcher can be replaced at the beginning of the next inning.
A player who enters the game must bat in the same spot in the batting order as that occupied by the person replaced. However, if two or more players enter the game at the same time, the manager may choose which spots they bat in; the manager must announce this decision to the umpire when they enter. If, for example, the manager brings a relief pitcher and a new catcher into the game at the same time, the new pitcher may bat in the former catcher's spot in the batting order, with the new catcher batting in the former pitcher's spot.
The Designated Hitter
In the American League, and at many other levels of baseball, there is a tenth player in the starting lineup known as the designated hitter (DH), who doesn't play in the field on the defense. The DH is designated to bat for the pitcher and may hit anywhere in a team's batting order.
A pinch hitter or pinch runner who is used for the designated hitter becomes the designated hitter, in turn. However, the DH must come to bat at least one time, unless the opposing team changes pitchers. That is, if the opposing team's starting pitcher is still in the game, a pinch hitter cannot be used for the DH in his first scheduled trip to the plate.
If the designated hitter is put into the game on defense, he continues to bat in the same spot in the batting order. The pitcher then bats in place of the defensive player who was replaced by the DH. From that time through the rest of the game, the team no longer has a designated hitter.