Ground Out
A ground ball fielded and thrown to first in time, and the out that carries the most hidden risk of a second one.
What it actually is. A ground out is a batted ball on the ground that a fielder collects and throws to first base before the runner arrives. In a scorebook it is written by position numbers, so 6-3 is shortstop to first base and 4-3 is second base to first.
What somebody who knows the game gets out of it. Ground balls are the safest batted ball for the defense and the least valuable for the hitter, because they almost never go for extra bases and they double a man up. That is why ground ball rate is a real pitcher skill worth paying for, and why the launch angle era is essentially a decision by hitters to stop hitting them. But a ground ball is also the one batted ball type that never becomes a home run, which is why sinkerballers survive in home run environments where fly ball pitchers do not.
The numbers worth knowing. Roughly 43 to 45 percent of balls in play are ground balls league wide. A ground ball becomes a hit about 24 percent of the time against about 22 percent for fly balls, but the fly ball's hits are worth far more.
What people get wrong about it. A productive out is a much smaller thing than it sounds. Moving a runner from second to third with nobody out gains a little, but the out itself costs more than the base gains in most situations, which the run expectancy table shows directly. A ground ball to the right side is a good habit, not a strategy.
At Little League and travel ball. At youth level the ground ball is the highest value batted ball, and this is the one place where youth and professional advice diverge. A hard ground ball at 10U produces errors, advances runners and scores runs at a rate that no fly ball does, so teaching a young hitter to hit the ball on the ground hard is correct at that age even though the same advice would be wrong at eighteen.
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