What is a Balk in Baseball

A balk is an illegal pitching action in baseball in which a pitcher deceives or misleads the baserunners — resulting in all baserunners advancing one base as a penalty.

A balk is an illegal motion made by a pitcher while in contact with the pitching rubber that deceives or is intended to deceive a baserunner. When an umpire calls a balk, all baserunners advance one base as a penalty — the most direct way pitching rules protect runners from deception.

Balk rules are among the most complex in baseball and among the least understood by casual fans. They exist because baserunners are entitled to make decisions (like stealing bases) based on pitcher behavior, and allowing pitchers to deceive runners unfairly would eliminate legit base-stealing strategy.

When Does a Balk Occur?

The rules are in MLB Rule 6.02. A balk is called when a pitcher:

1. Starts a pitching motion and doesn't deliver the pitch (fake to home plate)
2. Fakes a throw to first base without stepping toward first — must step before throwing; feigning the throw without stepping properly is a balk
3. Fails to come to a complete stop in the set position before delivering the pitch
4. Drops the ball while on the rubber, if the drop appears intentional or is fumbled
5. Pitches while not facing the batter
6. Makes a quick pitch (pitching before the batter is ready)
7. Steps toward an unoccupied base without a legitimate play reason
8. Throws to a base without disengaging the rubber first (in some cases)
9. Stands on or near the rubber without having the ball

The key concept: any deceptive motion while on the rubber that would confuse baserunners is a balk.

Balk Penalty

When a balk is called:

• All runners advance one base
• The pitch is nullified (dead ball)
• If the batter reached base or a run scored on the play anyway, the offense can choose the better outcome (keeps the result OR takes the balk advancement)

If there are no runners on base, a balk is typically not called — the rule exists to protect runners.

The Set Position and Balks

Most balks at professional levels involve the set position — the stance pitchers use when runners are on base:

• Pitcher must come to a complete, discernible stop with hands together before delivering the pitch
• Rushing through the stop (a "short stop") or not pausing long enough is the most commonly called balk
• The pause before pitching must be long enough to be visible — roughly one full second, though the rule says "complete stop"

Famous and Notable Balk Moments

Balks are relatively uncommon at the major league level but memorable when they occur in high-stakes moments:

• Dave Stewart of the Oakland A's was known for his deceptive delivery that drew balk calls
• Some pitchers with unusual delivery styles (like Jon Lester with his inability to throw to first) develop reputations around balk-related mechanics
• Youth and high school baseball environments see far more balks called, as pitchers learn proper mechanics

Balks and Pickoff Attempts

Pitchers may legally perform certain moves to prevent base-stealing:

• Step off the rubber (disengage) and then throw to any base freely — once off the rubber, balk rules don't apply
• Throw to first base — must step toward first in a direct motion
• Throw to second base — pitcher can spin and throw
• Throw to third base — must step toward third

A pickoff attempt is not a balk as long as the movements are legal. The pitcher must step toward the base before throwing and the throw must be made (or the motion must clearly be an attempt). Any faked pickoff to first base (without actually throwing) is specifically a balk; pickoff fakes to second and third are generally allowed as part of the game's strategy.