How automated ball-strike systems work, where they were tested from the Atlantic League in 2019 to the minors and spring training, and what the full and challenge versions each change.
How the batting-out-of-turn rule works, with worked examples, plus the appeal plays, time plays, protests and other rarely used rules that surprise fans when they finally come up.
What it means when a player is designated for assignment, how the seven-day clock works, who can claim him on waivers and when he can refuse an outright assignment to the minors. Written for fans who see the transaction line and want to know the rest.
How doubleheaders work, why some games last seven innings, what makes a shortened game official, and how a suspended game is resumed, with the history and the rules in plain language.
How the official scorer decides which runs count against a pitcher's ERA, by rebuilding the inning without errors, with worked examples, the passed-ball rule, relievers and the limits of the statistic.
How ejections work in baseball: the umpire's authority under the rules, what counts as arguing, the offenses that bring automatic removal, what happens afterward and how replay changed the argument.
A plain guide to the difference between a force out and a tag out, when a force is removed, why a run does or does not count on the third out, and how the timing play works, with worked examples.
The official scorer decides whether a ball is a hit or an error by asking what a fielder could do with ordinary effort. Learn the test, the common cases, what changes when the call is wrong and how rulings can be appealed.
How video review reached baseball in 2008 for home runs, how manager challenges began in 2014, what can and cannot be reviewed, and how managers decide when a challenge is worth spending.
How minor league options and optional assignments work, including the 20-day rule, the three option years, the fourth option and what happens when a player is out of options and a club wants him in the minors.
Interference is a foul by the offense, obstruction a foul by the defense. How each is judged for runners, batters, catchers and fielders, what Type A and Type B obstruction mean, and what the penalties are.
When a baseball game becomes official, what happens to the score when rain stops play mid-inning, how suspended games resume and why a tarp, a curfew or a tie changes the result. Worked examples for each case.
How major-league service time is counted in days, what six years and Super Two status unlock, how a salary arbitration hearing works, and why a call-up date can decide when a player reaches free agency.
A runner may advance on a caught fly ball only after retouching his base at the moment of the first touch. How tagging up works, how appeals punish early departures, and how the sacrifice fly is scored.
A plain-language guide to the balk: why the rule exists, the thirteen situations in the rulebook grouped by type with examples, what happens to runners, and how the 2023 disengagement limit changed it.
How the balls-and-strikes count works, how four balls and three strikes became the rules, what each of the twelve counts means for hitters and pitchers, and how walks and strikeouts have shifted since 1901.
How Major League Baseball limits payroll without a salary cap: the competitive balance tax thresholds and tiers, how payroll is measured, how revenue sharing moves money between clubs, and what the system does and does not do.
How the designated hitter works, why the American League adopted it in 1973, how the National League held out until 2022, what the numbers show about pitchers at the plate and how the Ohtani rule changed the position.
A third strike does not always end the at-bat. This guide explains when a batter may run after a dropped third strike, why first base and the number of outs matter, how the play is scored, and where the rule has decided games.
How the automatic runner on second base works in regular-season extra innings, why MLB introduced it in 2020, and how it changes bunting, intentional walks, bullpen use and the length of tie games.
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