Foul ball

In baseball, a foul ball is a batted ball that:

A foul fly shall be judged according to the relative position of the ball and the foul line, including the foul pole, and not as to whether the fielder is on foul or fair territory at the time he touches the ball.

Foul territory or foul ground is defined as the area of the field outside of the foul lines. The foul lines and foul poles are not part of foul territory.

In general, when a batted ball is ruled a foul ball, the ball is dead, all runners must return to their time-of-pitch base without liability to be put out, and the batter returns to home plate to continue his turn at bat. A strike is issued for the batter if he had fewer than two strikes. If the batter already has two strikes against him when he hits a foul ball, a strike is not issued unless the ball was bunted to become a foul ball, in which case a third strike is issued and a strikeout recorded for the batter and pitcher. A strike is, however, recorded for the pitcher for every foul ball the batter hits, regardless of the count. If any member of the fielding team catches a foul ball before it touches the ground or lands outside the field perimeter, the batter is out.

A foul ball is different from a foul tip, in which the ball makes contact with the bat, travels directly to the catcher's hands, and is caught. In this case, a strike is issued to the batter regardless of the ball/strike count, and runners may attempt to advance.

In a retractable or fixed roof baseball facility, a batted ball is a foul ball if it:

Rules vary from stadium to stadium for a ball striking the roof or suspended object in foul territory. Some consider such a ball to still be in flight, while others consider it a foul ball and dead from the time it strikes.

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