Agyroball is a rare type ofbaseball pitch used primarily by players inJapan. It is thrown with a spiral-like spin, similar to bullet from a rifle, or an American football pass.[1] This spin stabilizes the ball in flight, minimizing its deviation from a straight-line path to home plate.[2] The gyroball is sometimes confused with theshuuto, another pitch used in Japan.
The gyroball pitch was first developed by Ryutaro Himeno[a], a scientist who used computer simulations to model baseball flight paths, and Kazushi Tezuka[b], a baseball instructor who developed a throwing technique to pitch a gyroball.[3][4] The pitch is thrown with apronated motion of the arm and from alow arm angle, which Himeno and Tezuka argue reduces arm strain.[5]
This delivery creates a bullet-like spin on the ball, similar to the way anAmerican football spins when thrown.[1] The effect of this spin, which minimizes theMagnus force on the ball, is often misunderstood; a correctly-thrown gyroball will have minimal deflection from its straight path to home plate. Multiple early reports on the gyroball mistakenly claimed that the gyroball movedmore than a conventional pitch, behaving like an extremecurveball orslider.[3]
The unconventional spin of a gyroball is similar to the primary spin axis of someknuckleball pitches, such as those thrown byR. A. Dickey. However, knuckleballs are intended to minimize the ball's spin, increasing the effects of air drag to create an erratic flight-path, unlike the stabilizing spin of a gyroball.[6]
The gyroball is often confused with another primarily Japanese pitch, theshuuto. Some of this confusion stems from an error in an early article on the gyroball by baseball writerWill Carroll.[7] Although Carroll later corrected himself, the confusion still persists.
The unconventional spin may also lead a batter to mistakenly identify the pitch as a high-movementslider when the ball leaves the pitcher's hand, even though the pitch will end up moving like a fastball once in flight.[8]
Baseball Mogul was the first game to include the gyroball, in 2005.MLB 07: The Show andThe Bigs also include the pitch.Daisuke Matsuzaka is the only pitcher with a gyroball in each of these games.[citation needed] However, the movement of the pitch in the video game differs from the movement of the actual pitch, and Matsuzaka believes that the programmers mistook one of his other pitches for the gyroball.[9][verification needed] It is also an obtainable ability in the gameMLB Power Pros.[citation needed]
In the Japanesemanga andanime baseball seriesMajor, the protagonist, Goro, is known for his use of the gyroball pitch, which was his only pitch until he eventually adds aforkball to his repertoire.[citation needed]
Confusion about the nature of the gyroball, especially outside Japan, means that the list of pitchers who are believed to throw gyroballs is variable, depending on the source. Kazushi Tezuka citedShunsuke Watanabe,Tetsuro Kawajiri, andTomoki Hoshino as examples of Japanese gyroball pitchers when explaining the pitch to an American audience.[8]
Much of the discussion of the gyroball inMajor League Baseball circles stemmed fromDaisuke Matsuzaka, a Japanese pitcher who joined theBoston Red Sox in 2007. His slider was mislabeled as a gyroball in video analyses.[8] Matsuzaka had said he was trying to learn to throw the gyroball, but it is unclear if he ever actually threw it.[10]
Various other pitchers have claimed to be learning to throw gyroballs,[11] or have been claimed by others to throw gyroballs.[12][8] Tezuka claims that many children throw gyroballs unintentionally before their instructors modify their pitching form to produce more standard pitches.[13]