Hall of Fame knuckleballer Hoyt Wilhelm shows how he placed his fingers before a pitch.

A knuckleball or knuckler is a baseball pitch thrown to minimize the spin of the ball in flight, causing an erratic, unpredictable motion. The air flow over a seam of the ball causes the ball to transition from laminar to turbulent flow. This transition adds a deflecting force on the side of the baseball. This makes the pitch difficult for batters to hit, but also difficult for pitchers to control and catchers to catch; umpires are challenged as well, as the ball's irregular motion through the air makes it harder to call balls and strikes.[1] A pitcher who throws knuckleballs is known as a knuckleballer.


The origins of the knuckleball are unclear. Toad Ramsey of the Louisville Colonels in the old American Association—his pitch likely resembled the knuckle curve—and Eddie Cicotte of the major leagues' Chicago White Sox, who in 1908, was nicknamed "Knuckles", are two possible creators of the pitch.[2] Other accounts attribute the pitch's creation to Charles H. Druery, a pitcher for the Blue Ridge League.[3] In 1917, Druery taught the pitch to Eddie Rommel who became successful with the knuckleball for the Philadelphia Athletics.[4]

Other Languages
Deutsch: Knuckleball
français: Balle papillon
한국어: 너클볼
svenska: Knuckleball
中文: 蝴蝶球