Rule sets / NCAA / Unoccupied Base Balk
A pitcher may not throw to an unoccupied base unless the throw is part of a play to retire a runner.
If there is a runner or runners, a balk shall be called for the following action by a pitcher:
While in a pitching position, throws or feints a throw to an unoccupied base, except for the purpose of making a play.
TODO: describe the Unoccupied Base Balk in plain English.
TODO: explain the rationale — what the rule is protecting against.
TODO: what the pitcher should do differently.