Bigger Bases
Eighteen inches instead of fifteen, which shortened the distance between them by four and a half inches.
What it actually is. From 2023 the bases are eighteen inches square rather than fifteen. First and third moved slightly so their outfield edges stayed on the foul lines, and the practical result is that the distance a runner covers between bases fell by four and a half inches. The stated purpose was player safety at first base and around the bag at second.
What somebody who knows the game gets out of it. Four and a half inches sounds like nothing and is not nothing, because stolen base attempts are decided by hundredths of a second. Combined with the disengagement limit from the pitch clock, it produced the largest single season change in running behavior in decades. It is a clean demonstration that the balance between offense and defense in baseball sits on physical distances that were chosen arbitrarily in the nineteenth century.
The numbers worth knowing. 18 inches square, up from 15. Distance between first and second effectively 4.5 inches shorter. Stolen base attempts and success rates both rose sharply in the first season.
What people get wrong about it. The bases got bigger, the base paths did not. Ninety feet is still ninety feet between the corners of the bags as measured; what changed is where the usable edges are.
At Little League and travel ball. Youth base sizes vary by sanction and age and some already used larger bases. The safety reasoning is the same, and the double first base, an orange bag in foul territory for the runner, is common at youth level for exactly the collision reason.
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