Overview
The defensive shift repositions fielders based on batted ball direction, velocity, and angle data, placing more defenders where hits are most likely. The classic overshift places three infielders between first and second against left-handed pull hitters. MLB usage exploded in the late 2010s, reaching approximately 67,000 instances in 2022, but was regulated in 2023 after criticism that reduced hits diminished game appeal. NPB favors mild shifts with subtle adjustments rather than extreme overshifts, as NPB batters' superior contact ability and opposite-field hitting skill reduce the effectiveness of extreme positioning.