Illegal Pitch
An illegal pitch is any delivery that violates the rules — most commonly a pitch outside the legal arc window, a spin-thrown ball, or a release from an illegal position.
Common illegal-pitch violations in slow pitch include: arc too low (under 6 feet) or too high (over 12 feet); imparting intentional spin (turning the wrist sharply at release); a two-handed delivery; or pitching from outside the rubber. When an illegal pitch is called, the batter may take the pitch as a ball or choose to swing. Pitchers learn to read umpire tendencies and dial in their arc to stay legal and protect their team from free counts.
Example
The pitch rises to 14 feet — well above the maximum — and the umpire immediately signals "illegal pitch," giving the batter a ball.
Related terms
- Legal DeliveryA legal delivery in slow-pitch softball is a pitch that is released underhand with a smooth, continuous motion and arrives within the required arc height — typically between 6 and 12 feet — over the plate.
- Arc Height RegulationArc height regulation defines the required minimum and maximum height a slow-pitch delivery must reach — typically 6 to 12 feet — to be called a legal pitch.
- Strike Zone – Slow-PitchThe slow-pitch strike zone is the area over home plate between the batter's back knee and the top of the shoulders where a legal, properly arced pitch must land to be called a strike.
- Pitching RubberThe pitching rubber is the white rubber slab on the pitcher's mound from which the pitcher must begin and complete a legal delivery. Leaving or dragging off the rubber incorrectly results in an illegal pitch.
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