Fair ball (baseball)

How fair territory is defined

Fair territory is the portion of the playing field bounded by the two foul lines that extend from home plate past first and third base to the outfield fence, and by the lines themselves. The foul poles are vertical extensions of those lines; if a batted ball hits a foul pole it is considered fair.

Common conditions that make a batted ball fair

A batted ball is generally ruled fair if any of the following occur:

• It settles on fair ground between home and first base or between home and third base without being touched.
• While on or over fair territory it is touched by a fielder, umpire, or an object (for example, a glove or the ground).
• It bounds (bounces) past first or third base on or over fair territory.
• It touches first, second, or third base.
• It strikes the foul pole or the vertical extension of the foul line (this is treated as fair).

Examples and everyday situations

Typical fair-ball examples include grounders that land and roll in the infield between the bases, fly balls caught in fair territory, and line drives that pass over the infield on or above fair territory. A ball that initially travels over fair territory but then drops into foul territory beyond first or third base may still be ruled fair if it passed over the base in fair territory before going foul; conversely, a ball that goes foul before it passes the base is a foul ball unless touched in fair territory.

Relationship to other rules and notable distinctions

Some other rules interact with the fair/foul determination. The infield fly rule applies only to fair fly balls that can be caught with ordinary effort when runners occupy certain bases. A batted ball that is caught in flight in fair territory is an out even though it was a fair ball. Balls that leave the playing field in flight over fair territory are home runs; balls that bounce over an outfield fence typically become two-base awards under ground-rule double provisions. Umpires make fair/foul calls based on where the ball is in relation to fair territory at the relevant moments described above.

Understanding the fair-ball concept helps fans and players interpret plays that hinge on subtle placements and timing of the batted ball. Umpire judgment and the precise geometry of the field determine many borderline decisions.