pitcher throws to base where no runner is at

RulesMLB Umpire Manual

THROWING TO AN UNOCCUPIED BASE

Rule 6.02(a)(4): Official Baseball Rule 6.02(a)(4) provides that the pitcher be charged with a balk if, while in contact with the pitcher’s plate, he throws to an unoccupied base except for the purpose of making a play.     EXAMPLES: (1) Runners on first and second, pitcher in set position. Runner breaks for third base…