Section 5: Rules of Play

Per Rule 5.07(b), the pitch is considered delivered when the pitcher's arm passes the hip in the forward swing. Illegal pitches (e.g., a pitch delivered from an illegal position, a quick pitch, or a pitch while in an illegal position) result in a ...

Source: Rule 5.01, Rule 5.07, Rule 5.04, Rule 5.09, Rule 5.05, Rule 5.02

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