The Count
Balls first, strikes second, and the single biggest thing happening in an at bat that is not the pitch itself.
What it actually is. The count is the number of balls and the number of strikes on the hitter right now, said balls first. Four balls is a walk, three strikes is a strikeout, so the count runs from 0-0 to 3-2. A full count is 3-2: one more of either ends it. A foul ball with two strikes keeps the at bat alive and does not add a strike.
What somebody who knows the game gets out of it. The count is the leverage of the at bat and it is enormous. The same hitter facing the same pitcher is a different hitter at 2-0 than at 0-2, by more than the gap between the best and worst hitters in baseball. Ahead in the count a hitter can wait for a pitch in a zone he can drive; behind, he has to protect and swings at things he would otherwise take. That is why working the count is not passivity, and why the first pitch strike is the number pitching coaches actually care about.
The numbers worth knowing. League wide, a plate appearance that reaches 2-0 produces something around a .900 OPS and one that reaches 0-2 produces something closer to .400. First pitch strikes land around 60 percent of the time. A 3-0 pitch is taken more often than not, by rule of thumb rather than by rule.
What people get wrong about it. A full count is not neutral. It is a hitter's count with a strikeout attached: the pitcher has to throw something near the zone, but the hitter cannot foul off forever without eventually catching one he cannot handle. And 1-1 is the most underrated pitch in baseball, because the next one decides whether the at bat is a 2-1 or a 1-2, which are two different worlds.
At Little League and travel ball. At youth level the count means even more, because walks are the main source of baserunners. A pitcher who falls behind 2-0 at 10U is usually about to walk somebody, and a hitter taught to swing at anything close with two strikes will put more balls in play than his ability suggests. Coaches at that level who teach counting rather than mechanics tend to win more games.
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