What is a Balk? Definition, Rule Criteria, and Examples
A balk is an illegal pitching motion with runners on base that the umpire judges to deceive the runner — the ball is dead and every runner advances one base.
What Is a Balk in Baseball?
A balk is an illegal pitching motion with runners on base that the umpire judges to deceive the runner. When called, the ball is dead, no pitch is recorded, and every runner on base advances exactly one base — no exceptions, no manager's choice. It's one of the most-searched rules in baseball because it looks subtle, the umpire signals it without much explanation, and most fans never see two of them called the exact same way in a season.
The Rule: MLB Rule 6.02(a)
The official rulebook lists 13 specific actions that constitute a balk. The most common in modern games:
- No stop in the set position. From the stretch, the pitcher must come to a complete and discernible stop with hands together before delivering. A "quick pitch" without that pause is a balk.
- Starting and not completing the motion. Once the pitcher begins his delivery, he must finish it. Any flinch, hesitation, or aborted leg lift draws the call.
- Stepping toward home but throwing to a base. The pitcher's free foot must step toward whichever base he's throwing to.
- Faking a throw to first base from the rubber. Pitchers can fake to second or third from the rubber, but not to first.
- Throwing to an unoccupied base unless actively making a play.
- Dropping the ball on the rubber. Even an accidental drop is a balk.
- Pitching while not in contact with the rubber.
Penalty: dead ball, all runners advance one base. If the pitch is delivered and the batter reaches safely on a hit or walk — and every runner advances at least one base — the play stands and the balk is ignored.
A Real Example
Rich Hill, a long-time balk culprit, was called for eight balks in 2017 — the most in a single season since 1990. His unusual leg-kick pause from the stretch repeatedly drew warnings and calls. In the 2023 World Series, Adolis García scored from third on a balk by Bryce Elder, a quiet but decisive run in a one-run game.
League-wide, MLB averaged 195–220 balks per season before 2023. The pitch clock and new disengagement rules (a maximum of two pickoff attempts or step-offs per plate appearance) then drove the total to 393 balks in 2023 — nearly double the prior year — as pitchers adjusted to forced tempo and tighter pickoff economy.
Why It Matters
A balk is a free base. With a runner on second and one out, a balk turns the play into a runner on third with one out — sac-fly territory — raising the inning's expected runs by roughly 0.20. Across a full season, balks gift opposing teams 80–100 bases that no one earned with a bat.
For pitchers, balk-prone mechanics signal that runners can disrupt your timing, opening you up to extra steals and rattled tempo between pitches. Catchers and pitching coaches drill stop-and-set discipline harder than almost any other mechanical detail in the modern game.
Limitations and Misconceptions
Balks are not strict-liability. Umpires apply judgment, especially on the "complete stop" rule, and the same motion can be called differently by different crews. Replay does not cover balk calls — once they're called, they're final.
A common myth: a balk does not automatically score a runner from third. It only advances each runner one base. The only way a balk scores a runner is when the bases are loaded, forcing the runner on third home as part of the simultaneous one-base advance.
Related Terms
In Legends Deck
Balk-prone tendencies feed our pitcher card "Composure" rating. Pitchers with documented shaky stretch mechanics surrender slightly more balks and stolen bases in simulated innings with runners on, while pitchers with elite hold rates earn a defensive bonus when the opposing manager dials up a hit-and-run.