Pitching motions and balks
WBSC · 2025–2026Legal deliveries, pick-off moves and penalties with runners on base.
Legal delivery
The pitcher uses the windup or set position and follows its permitted movements. From the set position the required stop matters with runners aboard. A throw to a base must satisfy the stepping and throwing rules. Disengaging the rubber correctly changes the pitcher’s status; merely starting and abandoning a delivery does not.
Balks and illegal pitches
Deceptive or prohibited pitching actions with runners can be balks, generally awarding advancement under the balk rule. With empty bases, comparable illegal actions may instead produce a ball. Some balk plays continue if the batter and every runner advance sufficiently. Ball alteration, foreign substances and intentionally pitching at a batter carry separate penalties.
Sources & approach ↗