Balk
BKAn illegal motion by the pitcher with runners on base, penalized by advancing every runner one base.
A balk is any illegal deceptive motion by a pitcher while runners are on base. The penalty is automatic: every runner advances one base. With nobody on, the same motion is simply a ball.
The rule exists to stop the pitcher deceiving a runner about whether a pitch is coming. The common versions are starting the delivery and stopping, failing to come to a complete stop from the set position, and stepping toward a base without actually throwing there.
Youth baseball treats it gently, and it varies by ruleset. Little League issues a warning on a first offense for younger divisions rather than enforcing the penalty immediately, on the reasonable grounds that a twelve-year-old learning the set position is not deceiving anyone on purpose.
Bleacher Notes advances every runner one base on a balk and records it against the pitcher, applying whichever warning convention your ruleset specifies.
What happens on a balk?
Every runner on base advances one base. If no runners are on, the pitch is called a ball instead and no penalty applies.
Is there a balk rule in Little League?
Yes, though younger divisions typically issue a warning on a first offense rather than enforcing the advance immediately. Check your division's ruleset, since this is one of the more commonly modified rules.
Let the scorebook keep itself.
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