A knuckleball (or knuckler for short) is a baseball pitch thrown so as to minimize the spin of the ball in flight. The lack of spin creates a chaotic airflow over the stitched seams of the baseball and produces an erratic, unpredictable motion. This makes the pitch difficult for batters to hit, but also difficult for pitchers to control. The challenge also extends to the catcher who must make an attempt to catch the pitch, and the umpire who must determine whether it was a strike or a ball.
The identity of the first pitcher to throw a knuckleball is uncertain, but it appears to have been developed in the early 20th century. Lew "Hicks" Moren of the Philadelphia Phillies was credited as its inventor by the New York Press in 1908. However, Eddie Cicotte apparently also came up with the pitch while at Indianapolis in 1906, and brought it to the majors with him two years later. Since Cicotte had a much more successful career (and also gained later notoriety as one of the Black Sox), his name is the one most often associated with the invention of the pitch today.
Grip and motion of knuckleball
As used by Cicotte, the knuckleball was originally thrown by holding the ball with the knuckles, hence the name of the pitch. Ed Summers, an Indianapolis 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 actually more commonly used today by pitchers who throw the knuckleball.
Regardless of how the pitch is gripped, the purpose of the knuckleball is to avoid the rotational spin normally created by the act of throwing a ball. In the absence of this rotation, the ball's trajectory is significantly affected by variations in airflow caused by differences between the smooth surface of the ball and the stitching of its seams. The asymmetric drag that results will tend to deflect the trajectory toward the side with the stitches.
Over the distance from the pitcher's mound to home plate, the effect of these forces is that the knuckleball can "flutter", or actually curve in two opposite directions over its flight. A pitch thrown completely without spin is actually less desirable, however, than one with only a very slight spin (so that the ball completes perhaps between one-half and one rotation on its way from the pitcher to the batter). This will cause the position of the stitches, and therefore the drag that gives the ball its motion, to change somewhat as the ball travels, thus making its flight even more erratic. Even a ball thrown without rotation will "flutter" somewhat, due to the 'apparent wind' it feels as its trajectory changes throughout its flight path.
A hazard of the knuckleball is evident in one sportscaster's desciption of the ball's behavior: "It either dances in or prances out." As a safety measure (for their earned run average) some pitchers will induce a slight topspin so that if no force causes the ball to dance it will move downward in flight. At the speed a knuckleball is thrown the batter is unlikely to swing and miss for a strike, but a slow ball that bounces is very difficult to hit and relatively easy for the catcher to block.
Naming and relationship to other pitches
Since it developed during a period when the spitball was legal and commonly used, and was similarly surprising in its motion, the knuckleball was sometimes called the "dry spitter". Cicotte was widely reported to throw both the knuckleball and a variant on the spitball known as a "shine ball" (because he would "shine" one side of a dirty ball by rubbing it on his uniform). However, Cicotte called the shine ball "a pure freak of the imagination", claiming that he did this to disconcert hitters but that the pitch was still a knuckleball.
Other names for the knuckleball have generally alluded to its motion and slower speed. These include the flutterball, the floater, the dancer, the butterfly ball, the ghostball, and the bug.
The knuckle curve has a somewhat similar name because of the grip used to throw it (also with the knuckles or fingernails), but it is generally thrown harder and with spin. The resulting motion of the pitch more closely resembles a curveball, which explains the combination name. Toad Ramsey, a pitcher from 1885-1890, is credited in some later sources with being the first knuckleballer, apparently based primarily on accounts of how he gripped the ball; however, based on more contemporary descriptions of his pitch as an "immense drop ball", it may be that his pitch was a form of knuckle curve. Two later pitchers, Jesse Haines and Freddie Fitzsimmons, were sometimes characterized as knuckleball pitchers even by their contemporaries, but in their cases this again refers to a harder-thrown, curving pitch that would probably not be called a knuckleball today.
Use of the knuckleball in pitching
When originally developed, the knuckleball was used by a number of pitchers as simply one pitch in their repertoire, usually as part of changing speeds from their fastball. It is almost never used in a mixed repertoire today, however, and some believe that to throw the knuckleball effectively with some semblance of control over the pitch, one must throw it more or less exclusively. At the same time, pitchers rarely focus on the knuckleball if they have reasonable skill with more standard pitches, so knuckleball pitchers have become quite rare.
However, the knuckleball does provide some advantages to its practitioners. It does not need to be thrown hard (in fact, throwing too hard may diminish its effectiveness), and is therefore less taxing on the arm. This means knuckleball pitchers can throw more innings than orthodox pitchers, and are able to pitch more frequently because they require less time to recover after having pitched. The lower physical strain also gives them the potential for greater career longevity, as some have continued to pitch professionally well into their forties. In addition, some pitchers (such as Jim Bouton) have had success as knuckleballers after their ability to throw hard declined.
Hoyt Wilhelm and Phil Niekro, two pitchers who primarily relied on the knuckleball, have been inducted into the Baseball Hall of Fame (Haines is also in the Hall of Fame). Niekro was given the nickname "Knucksie" during his career. Other prominent knuckleball pitchers have included Joe Niekro (Phil's brother), Charlie Hough, Wilbur Wood, Tom Candiotti, Bob Purkey and Tim Wakefield. During the 1945 season, with talent depleted by call-ups to fight in World War II, the Washington Senators had a pitching rotation which included four knuckleball pitchers (Dutch Leonard, Johnny Niggeling, Mickey "Itsy Bitsy" Haefner and Roger Wolff) who combined for 60 complete games and 60 wins, carrying the Senators to second place.
Catching the knuckleball
The unpredictable motion of the knuckleball makes it one of the most difficult pitches for a catcher to handle. Catchers tend to be charged with a significantly higher number of passed balls when a knuckleball pitcher is on the mound. A team will sometimes employ a catcher solely for games started by a knuckleballer. The Boston Red Sox did this fairly systematically in their 2004 world championship season, with Doug Mirabelli regularly catching in place of Jason Varitek when Tim Wakefield was pitching.
Quotes on catching the knuckleball:
- "You don't catch a knuckleball, you defend against it" -- manager and former catcher Joe Torre
- "Wait'll it stops rolling, then go pick it up." -- broadcaster and former catcher Bob Uecker
- "There are two theories on hitting a knuckleball. Unfortunately, neither of them works." -- famed hitting coach Charlie Lau
- "You know, catching the knuckleball, it's like trying to catch a fly with a chopstick." -- catcher Jason Varitek
- "If it's high, let it fly. If it's low, let it go." -- New York Yankee hitters describing the approach to hitting the knuckleball
- "Throwing a knuckleball for a strike is like throwing a butterfly with hiccups across the street into your neighbor's mailbox." -- Willie Stargell
- Adair, Robert K. (1990). The Physics of Baseball. New York: Harper & Row. ISBN 0-06-096461-8.
- James, Bill & Rob Neyer (2004). The Neyer/James Guide to Pitchers. New York: Fireside. ISBN 0-7432-6158-5.
- Project Knuckleball, an article in The New Yorker about the history of the knuckleball and contemporary knuckleball pitchers.
- Knuckleball Headquarters - Comprehensive collection of information about the pitch and those who have thrown it