Utility Players and the Bench
The four or five men not starting, and the reason modern managers have less room to move than old ones did.
What it actually is. The bench is the position players not in the starting lineup, usually four or five men on a 26 man roster: a backup catcher, an infielder, an outfielder and one or two others. A utility player can cover several positions competently; a super utility can cover the hard ones. A pinch hitter bats in place of somebody due up, and the man he replaces is out of the game.
What somebody who knows the game gets out of it. The bench shrank because the bullpen grew, and that changed the game more than people notice. A manager with a five man bench could pinch hit for a struggling starter in the sixth; a manager with three cannot, because he needs a backup catcher in reserve and one man for a defensive replacement. That is why the double switch has nearly disappeared, why platoons are built into the lineup rather than deployed in the seventh, and why versatility became the most valuable trait a fringe roster player can have.
The numbers worth knowing. A 26 man roster typically carries 13 pitchers, which leaves 13 position players, which leaves four or five on the bench once the nine starters are set. A pinch hitter historically performs about ten to twenty points of OPS below his normal level, coming in cold.
What people get wrong about it. A pinch hitter is a permanent substitution in professional baseball. There is no returning to the game, which is what makes every bench decision one way, and it is the reason a manager sometimes leaves a poor hitter in: not because he thinks he will hit, but because using the last bat means no defensive options later.
At Little League and travel ball. Almost all youth rules allow free re-entry for starters, and many use a continuous batting order where everybody hits regardless. That removes most of the strategy and replaces it with a different one, which is playing time management, and the rules about it vary by sanction more than any other area.
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