In baseball and softball, an uncaught third strike (sometimes referred to as dropped third strike or non-caught third strike) occurs when the catcher fails to cleanly catch a pitch for the third strike of a plate appearance. In Major League Baseball (MLB), the specific rules concerning the uncaught third strike are addressed in Rules 5.05 and 5.09 of the Official Baseball Rules: This is one of the oldest rules in modern baseball, dating at least to the Knickerbocker Rules of 1845: "Three balls being struck at and missed and the last one caught, is a hand-out."