Knuckle ball

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.

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. Other accounts attribute the pitch's creation to Charles H. Druery, a pitcher for the Blue Ridge League. In 1917, Druery taught the pitch to Eddie Rommel who became successful with the knuckleball for the Philadelphia Athletics.

As used by Cicotte, the knuckleball was originally thrown by holding the ball with the knuckles, hence the name of the pitch. Ed Summers, a Pittsburgh teammate of Cicotte who adopted the pitch and helped develop it, modified this by holding the ball with his fingertips and using the thumb for balance. This grip can also include digging the fingernails into the surface of the ball. The fingertip grip is more commonly used today by knuckleball pitchers, like retired Boston Red Sox pitcher Tim Wakefield, who had a knuckleball with a lot of movement. There are other prominent knuckleball pitchers like Hall of Famer Phil Niekro, who had a very effective knuckler and knuckle curve, and current Atlanta Braves pitcher R.A. Dickey. However, young pitchers with smaller hands tend to throw the knuckleball with their knuckles. Sometimes young players will throw the knuckleball with their knuckles flat against the ball, giving it less spin but also making it difficult to throw any significant distance.

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