
A knuckleball or knuckler is a
baseball
Baseball is a bat-and-ball sport played between two teams of nine players each, taking turns batting and fielding. The game occurs over the course of several plays, with each play generally beginning when a player on the fielding ...
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 change from
laminar to
turbulent flow. This change adds a deflecting force to the baseball, making it difficult for
batters to hit but also difficult for
pitcher
In baseball, the pitcher is the player who throws ("pitches") the Baseball (ball), baseball from the pitcher's mound toward the catcher to begin each play, with the goal of out (baseball), retiring a batter (baseball), batter, who attempts to e ...
s to control and
catcher
Catcher is a position in baseball and softball. When a batter takes their turn to hit, the catcher crouches behind home plate, in front of the (home) umpire, and receives the ball from the pitcher. In addition to this primary duty, the catcher ...
s to catch; umpires are challenged as well, as the ball's irregular motion through the air makes it harder to call
balls and
strikes
Strike may refer to:
People
*Strike (surname)
Physical confrontation or removal
*Strike (attack), attack with an inanimate object or a part of the human body intended to cause harm
*Airstrike, military strike by air forces on either a suspected ...
.
[Hoffman, Benjamin]
"Not So Easy on the Eyes"
''New York Times
''The New York Times'' (''the Times'', ''NYT'', or the Gray Lady) is a daily newspaper based in New York City with a worldwide readership reported in 2020 to comprise a declining 840,000 paid print subscribers, and a growing 6 million paid ...
'' (June 23, 2012) A pitcher who throws knuckleballs is known as a
knuckleballer.
Origins
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
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 in the
Blue Ridge League. In 1917, Druery taught the pitch to
Eddie Rommel who became successful with it for the Philadelphia Athletics.
Grip and motion
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 it by holding the ball with his fingertips and using the
thumb
The thumb is the first digit of the hand, next to the index finger. When a person is standing in the medical anatomical position (where the palm is facing to the front), the thumb is the outermost digit. The Medical Latin English noun for thu ...
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
Cy Young Award
The Cy Young Award is given annually to the best pitchers in Major League Baseball (MLB), one each for the American League (AL) and National League (NL). The award was first introduced in 1956 by Baseball Commissioner Ford Frick in honor of Ha ...
winning 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.
Regardless of how the ball is gripped, the purpose of the knuckleball is to have the least possible amount of rotational spin. Created by the act of throwing a ball, 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
Drag or The Drag may refer to:
Places
* Drag, Norway, a village in Tysfjord municipality, Nordland, Norway
* ''Drág'', the Hungarian name for Dragu Commune in Sălaj County, Romania
* Drag (Austin, Texas), the portion of Guadalupe Street adj ...
that results tends 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, dance, jiggle, or curve in two different directions during its flight. A pitch thrown completely without spin is less desirable, however, than one with a very slight spin. The ball completes between one-quarter and one-half a rotation on its way from the pitcher to the batter; the position of the stitches changes as the ball travels, affecting the drag that gives the ball its motion, thus making its flight erratic. Even a ball thrown without rotation will "flutter", due to the "apparent wind" it feels as its trajectory changes throughout its flight path.
Hitting a knuckleball is different enough from other aspects of baseball that players specifically prepare for the pitch during batting practice before games they expect it in.
According to physicist
Robert Adair, due to the physiological limitation of human
reaction time, a
breaking knuckleball may be impossible to hit except by luck. If a knuckleball does not change direction in mid-flight, however, then it is easy to hit due to its lack of speed. (A common phrase for hitting a knuckleball is "if it's low, let it go; if it's high, let it fly"; meaning that a batter should attempt to hit a knuckleball only if it crosses the plate high in the strike zone due to lack of break.) Since it typically only travels , far slower than the average major league fastball , it can be hit very hard if there is no movement. One 2007 study offered evidence for this conclusion. To reduce the chances of having the knuckleball get hit for a
home run
In baseball, a home run (abbreviated HR) is scored when the ball is hit in such a way that the batter is able to circle the bases and reach home plate safely in one play without any errors being committed by the defensive team. A home run is ...
, some pitchers will impart a slight
topspin so that if no force causes the ball to dance, it will move downward in flight. Another drawback is that runners on base can usually advance more easily than if a conventional pitcher is on the mound. This is due to both the knuckleball's low average speed and its erratic movement, which force the catcher to keep focusing on the ball even after the runners start stealing their next bases. However, since a typical major league starting rotation exceeds the length of a series against any one opponent, one way a manager can mitigate this disadvantage is to adjust his team's pitching rotation so as to eliminate (or at least minimize) games in which a knuckleballer would pitch against teams with a preponderance of fast baserunners.
A paper presented at the 2012 Conference of the International Sports Engineering Association argues, based on
PITCHf/x PITCHf/x is a system created and maintained by Sportvision that tracks the speeds and trajectories of pitched baseballs. This system, which made its debut in the 2006 Major League Baseball (MLB) postseason, is installed in every MLB stadium. The ...
data, that knuckleballs do not make large and abrupt changes in their trajectories on the way to home plate—or at least, no more abrupt than a normal pitch. It speculates that the appearance of abrupt shifting may be due to the ''unpredictability'' of the changes in direction.
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 and 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 name for the pitch used by French language game commentators employed by the
Montreal Expos), 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 to 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 it again refers to a harder-thrown, curving pitch that would probably not be called a knuckleball today. Historically, the term "knuckle curve" had a usage that was different from what it has in the game today. Many current pitchers throw a curveball using a grip with the index finger touching the ball with the knuckle or fingertip (also called a spike curve). This modern pitch is unrelated to the knuckleball.
Rarity
, only about 70 Major League Baseball pitchers have regularly used the knuckleball during their careers, and its use has become rarer over time. This can be attributed to a variety of factors. The first is
selection bias in
scouting. Because the speed of any prospect's pitch is one of the quickest and easiest metrics in judging the skill of the prospect, the knuckleball, which is thrown slower than any other pitch, gets overlooked.
Tim Wakefield argues that "The problem is that
aseballis so radar gun-oriented." Former knuckleballer and pitching coach
Charlie Hough says that the increased rarity of the knuckleball is due to scouts increasingly looking only for the best arm.
This effect is increasing over time as the modern game continues to emphasize power in pitching and average pitch speed increases.
Hoyt Wilhelm,
Phil Niekro, and
Jesse Haines, three pitchers who primarily relied on the knuckleball, have been inducted into the
Baseball Hall of Fame
The National Baseball Hall of Fame and Museum is a history museum and hall of fame in Cooperstown, New York, operated by private interests. It serves as the central point of the history of baseball in the United States and displays baseball ...
. Additionally,
Ted Lyons, another member of the Hall of Fame, relied heavily on the knuckleball after injuring his arm in 1931. Niekro was given the nickname "Knucksie" during his career. Other prominent knuckleball pitchers have included
Joe Niekro (Phil's brother),
Charlie Hough,
Dave Jolly,
Ben Flowers,
Wilbur Wood,
Barney Schultz,
Tom Candiotti,
Bob Purkey,
Steve Sparks,
Eddie Rommel,
Tim Wakefield,
Steven Wright, and Dickey. 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
game
A game is a structured form of play, usually undertaken for entertainment or fun, and sometimes used as an educational tool. Many games are also considered to be work (such as professional players of spectator sports or games) or art (su ...
s and 60 wins, carrying the Senators to second place.
In November 2008, it was announced that 16-year-old knuckleballer
Eri Yoshida was drafted as the first woman ever to play in Japanese professional baseball for the
Kobe 9 Cruise of the
Kansai Independent Baseball League. On March 2, 2010, she trained with Tim Wakefield at the
Boston Red Sox
The Boston Red Sox are an American professional baseball team based in Boston. The Red Sox compete in Major League Baseball (MLB) as a member club of the American League (AL) East division. Founded in as one of the American League's eig ...
minor-league training facility. And on April 8, 2010, she signed with the
Chico Outlaws, debuting on May 29, 2010.
Another factor contributing to the rarity of the knuckleball is the difficulty of throwing the pitch.
R. A. Dickey estimates that it takes at least a year to grasp its fundamentals. The knuckleball is radically different from any other pitch in a pitcher's arsenal, being less predictable and difficult to control. It is for this reason that the knuckleball is widely regarded as unreliable, and knuckleball pitchers are prone to extended slumps, such as when Tim Wakefield was released from the Pirates in a mid-career slump during spring training in 1995.
Another reason for the difficulty of the knuckleball is due to the
network effect. Because there are so few knuckleball pitchers, the resources for learning and improving the knuckleball are few compared to more common pitches. Pitching coaches often struggle with knuckleball pitchers due to a lack of experience with the pitch. "I think the hardest thing for me is just the alone-ness that you feel sometimes because nobody else really does it," said Wakefield.
Coaches have also been seen as a barrier to succeeding with the knuckleball.
Jim Bouton said, "coaches don't respect it. You can pitch seven good innings with a knuckleball, and as soon as you walk a guy they go, 'See, there's that damn knuckleball.'" R. A. Dickey argues that, "for most managers, it takes a special manager to be able to really trust it – the bad and the good of it. Coaches are quick to banish the pitch after one bad outing. This was common due to the amount of practice one must put into the pitch. And traditionally, if you look at Tim Wakefield, Joe and Phil Niekro, Tom Candiotti, Wilbur Wood, Hoyt Wilhelm and all the guys that threw it, through their success they had guys who really believed in what it could do long-term and committed to giving them the ball every fifth day to do it."
In 1991, Hall of Fame catcher Rick Ferrell was quoted as saying, "I think the knuckleball is fading out." Ferrell knew knuckleballs: he had the task of being the Washington Senators catcher in 1944–45, when the Senators had four knuckleball pitchers in their starting rotation. Furthermore, other factors, such as a dearth of knuckleball teachers and the dramatic increase in the running game — base stealing is often easier against knuckleball pitchers — may be contributing to its demise.
Perhaps as a result, knuckleball pitchers often view themselves as members of an exclusive club, with its own
uniform number (49, first worn by Wilhelm) and leader (Phil Niekro, whom ''The New Yorker'' in 2004 called "the undisputed Grand Poobah" of the group after Wilhelm's death). Because they cannot discuss pitching with non knuckleball-using teammates, they often share tips and insights even if on competing teams, and believe that they have a responsibility to help younger players develop the pitch.
When, in 2012, R. A. Dickey became the first
Cy Young Award
The Cy Young Award is given annually to the best pitchers in Major League Baseball (MLB), one each for the American League (AL) and National League (NL). The award was first introduced in 1956 by Baseball Commissioner Ford Frick in honor of Ha ...
-winning knuckleball pitcher, he called the award "a victory for … the knuckleball fraternity", and of the dozens of phone calls he received after the announcement, Niekro's was the only one he answered.
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
The fastball is the most common type of pitch thrown by pitchers in baseball and softball. " Power pitchers," such as former American major leaguers Nolan Ryan and Roger Clemens, rely on speed to prevent the ball from being hit, and have t ...
. 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. Unlike conventional pitches, which perform fast results without much exertion, a knuckleball pitcher must train his body and muscle memory to be able to execute a 65 mph pitch with less than one rotation.
,
Steven Wright of the
Boston Red Sox
The Boston Red Sox are an American professional baseball team based in Boston. The Red Sox compete in Major League Baseball (MLB) as a member club of the American League (AL) East division. Founded in as one of the American League's eig ...
was considered to be the last active knuckleballer in the MLB; he has since been released from the team.
Mickey Jannis of the
Baltimore Orioles
The Baltimore Orioles are an American professional baseball team based in Baltimore. The Orioles compete in Major League Baseball (MLB) as a member club of the American League (AL) East division. As one of the American League's eight charter ...
organization also throws the knuckleball, and made his major league debut on June 23, 2021.
On September 18, 2020, the first knuckleball thrown in 2020 was by the
New York Mets'
Todd Frazier, normally a third baseman, in a 15-2 blowout loss to
Atlanta Braves
The Atlanta Braves are an American professional baseball team based in the Atlanta metropolitan area. The Braves compete in Major League Baseball (MLB) as a member club of the National League (NL) East division. The Braves were founded in B ...
.
Among
position players making pitching appearances, those who have utilized the knuckleball include
Wade Boggs,
Danny Worth,
Alex Blandino
Alessandre Blandino (born November 6, 1992) is a Nicaraguan American professional baseball infielder who is currently a free agent. He has played in Major League Baseball (MLB) for the Cincinnati Reds. He played college baseball at Stanford and wa ...
, and
Ernie Clement.
Use in pitching
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. Knuckleball pitchers can throw more
innings than other pitchers, and, requiring less time to recover after pitching, can pitch more frequently. The lower physical strain also fosters longer careers. Some knuckleballers have continued to pitch professionally well into their forties:
Tim Wakefield,
Hoyt Wilhelm,
R. A. Dickey,
Charlie Hough,
Tom Candiotti, and the brothers
Phil Niekro and
Joe Niekro.
Pitchers like Bouton have found success as knuckleballers after their ability to throw hard declined. Indeed, Bouton's famous best-selling book ''
Ball Four'' (1970), while scandalous at the time for its unvarnished and often uncomplimentary portrayal of player behavior and coaching small-mindedness, is primarily a tale of the ups and downs of trying to hang on in the major leagues as a knuckleball pitcher.
Catching
As with hitters, the unpredictable motion of the knuckleball makes it one of the most difficult pitches for catchers to handle, and they tend to be charged with a significantly higher number of
passed balls. Former catcher
Bob Uecker, who caught for Phil Niekro, said, "The way to catch a knuckleball is to wait until it stops rolling and pick it up."
Bouton said, "Catchers hate it. Nobody likes to warm up with you." According to Adair, the 150 ms minimum human reaction time may be too slow to adjust to a knuckleball's changing direction.
A team will sometimes employ a catcher solely for games started by a knuckleballer. The "knuckleball catcher" is equipped with an oversized knuckleball catcher's mitt,
similar to a
first baseman's glove
A baseball glove or mitt is a large glove (traditionally made of leather, today other options do exist) worn by baseball players of
the defending team, which assists players in catching and fielding balls hit by a batter or thrown by a teammate ...
;
Doug Mirabelli, formerly of the
Red Sox, used a
softball
Softball is a game similar to baseball played with a larger ball on a smaller field. Softball is played competitively at club levels, the college level, and the professional level. The game was first created in 1887 in Chicago by George Hanc ...
catcher's mitt. The
Boston Red Sox
The Boston Red Sox are an American professional baseball team based in Boston. The Red Sox compete in Major League Baseball (MLB) as a member club of the American League (AL) East division. Founded in as one of the American League's eig ...
, in their
2004
2004 was designated as an International Year of Rice by the United Nations, and the International Year to Commemorate the Struggle Against Slavery and its Abolition (by UNESCO).
Events January
* January 3 – Flash Airlines Flight 60 ...
world championship season, had Mirabelli regularly catching in place of
Jason Varitek when
Tim Wakefield was pitching. This use of a "specialist" catcher continued into the 2008 season following the signing of
Kevin Cash, and 2009 saw
George Kottaras
George Kottaras ( ; born May 10, 1983) is a Canadian former professional baseball catcher. He played in Major League Baseball (MLB) for the Boston Red Sox, Milwaukee Brewers, Oakland Athletics, Kansas City Royals, Cleveland Indians, St. Louis Card ...
fulfill this role. On August 26, the first time
Victor Martinez caught Wakefield, he used a
first baseman's glove
A baseball glove or mitt is a large glove (traditionally made of leather, today other options do exist) worn by baseball players of
the defending team, which assists players in catching and fielding balls hit by a batter or thrown by a teammate ...
, instead of a regular catcher's mitt. For a catcher, a key disadvantage to using a first baseman's glove mitt is that they are not designed for easy extraction of the ball from the glove, making it harder to prevent baserunners from
stealing
Theft is the act of taking another person's property or services without that person's permission or consent with the intent to deprive the rightful owner of it. The word ''theft'' is also used as a synonym or informal shorthand term for som ...
.
On occasion, teams have traded knuckleball pitchers and their catchers in the same transaction. In baseball terminology the pitcher and catcher together are known as a "battery", and having a catcher experienced in catching a knuckleball pitcher is preferable, so the trade of pitcher and catcher together is sometimes referred to as a "batteries included" trade. For example,
Josh Thole and
Mike Nickeas went with Dickey when the pitcher was traded to the
Toronto Blue Jays in late 2012, and the team later signed
Henry Blanco, who also caught for Dickey.
The record for passed balls in an inning (4) was first set by
Ray Katt of the
New York Giants
The New York Giants are a professional American football team based in the New York metropolitan area. The Giants compete in the National Football League (NFL) as a member club of the league's National Football Conference (NFC) East divisio ...
in 1954, catching Hoyt Wilhelm.
It was tied by
Geno Petralli of the Texas Rangers in 1987 while trying to catch knuckleball pitcher
Charlie Hough, and tied again in 2013 when
Ryan Lavarnway of the Boston Red Sox had four in the first inning, catching knuckleballer
Steven Wright in Wright's first major league start.
Varitek holds the postseason record with three passed balls in the 13th inning of
Game 5 of the 2004 American League Championship Series while catching Wakefield.
In 2013,
J. P. Arencibia set a
Toronto Blue Jays franchise record by allowing four passed balls in the season opener (a 4–2 loss) while catching for knuckleballer R. A. Dickey. He never caught for Dickey again.
Use in other sports
Cricket
The knuckleball is also employed by
cricket
Cricket is a bat-and-ball game played between two teams of eleven players on a field at the centre of which is a pitch with a wicket at each end, each comprising two bails balanced on three stumps. The batting side scores runs by st ...
fast bowlers
Zaheer Khan
Zaheer Khan (born 8 October 1978) is an Indian former professional cricketer who played all forms of the game for the Indian national team from 2000 till 2014. He is a fast-medium left-arm bowler. He was the second-most successful Indian pace ...
,
Bhuvneshwar Kumar and
Andrew Tye
Andrew James Tye (born 12 December 1986) is an Australian cricketer who plays One Day Internationals (ODIs) and Twenty20 Internationals (T20Is) for the Australian national cricket team. At the domestic level he plays for Western Australia a ...
as their slower delivery. The physics of the operation are largely the same. However, the seam on a cricket ball is equatorial, and thus the extent of erratic movement is reduced due to the symmetry (at least in the conventional release position where the planes of the ball's trajectory and the seam are nearly co-planar). In addition, the lack of backspin does shorten the length of the delivery, and also tends to make the ball skid off the pitch—faster than it would come off a normal delivery.
Volleyball
In
volleyball
Volleyball is a team sport in which two teams of six players are separated by a net. Each team tries to score points by grounding a ball on the other team's court under organized rules. It has been a part of the official program of the Summ ...
, the
float serve involves hitting the volleyball in such a way to minimize the rotation of the ball, causing unpredictability in the ball's movement. When done correctly, the float serve is hard for opponents to predict where the ball will end up, thus rendering it hard to pass.
Association football
In
association football
Association football, more commonly known as football or soccer, is a team sport played between two teams of 11 players who primarily use their feet to propel the ball around a rectangular field called a pitch. The objective of the game is t ...
(soccer), the method of
striking
Strike may refer to:
People
*Strike (surname)
Physical confrontation or removal
*Strike (attack), attack with an inanimate object or a part of the human body intended to cause harm
*Airstrike, military strike by air forces on either a suspected ...
the ball so that it produces almost no
spinning motion during its flight has been colloquially described as "knuckleballing" by commentators, due to the ball's motion that resembles a baseball thrown with a knuckleball pitch. This shooting technique is frequently used by players for long-range shots and
free kicks. A successful knuckleball shot will move, dip, or wobble in the air unpredictably, making it difficult for the goalkeeper to save.
This technique has also been described as the "dry leaf" or "dead leaf" ("folha seca" in Portuguese),
the "tomahawk",
or even "the accursed" ("maledetta" in Italian).
One of the main proponents of this shooting technique was Brazilian playmaker
Juninho Pernambucano, who popularised it in particular during his time with
Lyon
Lyon,, ; Occitan: ''Lion'', hist. ''Lionés'' also spelled in English as Lyons, is the third-largest city and second-largest metropolitan area of France. It is located at the confluence of the rivers Rhône and Saône, to the northwest of ...
in the mid 2000s; however, it is commonly thought to have been invented by compatriot
Didi,
["Kings of the free-kick"](_blank)
FIFA.com. Retrieved 20 May 2014 although Italian forward
Giuseppe Meazza before him is also credited with using the technique.
This technique has also been used and even adapted by several other players, such as
Andrea Pirlo,
Ronaldinho,
Cristiano Ronaldo,
Didier Drogba,
Marcus Rashford,
Gareth Bale
Gareth Frank Bale (born 16 July 1989) is a Welsh professional footballer who plays as a winger for Major League Soccer club Los Angeles FC and the Wales national team. He is widely regarded as one of the greatest wingers of his generation ...
,
and
Barbara Bonansea
Barbara Bonansea (born 13 June 1991) is an Italian professional footballer who plays as a forward or midfielder for Serie A club Juventus FC and the Italy women's national team.
Club career
After more than a 100 games for A.C.F. Torino, Bona ...
.
See also
*
List of knuckleball pitchers
*''
Knuckleball!
''Knuckleball!'' is a 2012 documentary film that follows the 2011 seasons of Tim Wakefield and R. A. Dickey, Major League Baseball's only knuckleball pitchers that year. It was released in theaters on September 20, 2012 and on DVD on April 2, 20 ...
'', 2012 documentary
References
Notes
Bibliography
*
*
*
External links
Knuckleball Headquarters– Comprehensive collection of information about the pitch and those who have thrown it
– A list of just about everyone who's thrown the pitch in the major leagues, with links to each player's career stats.
NPR.org on the Red Sox's re-acquisition of Doug Mirabelli
{{Baseball
Baseball pitches