In baseball, a pitch is the act of throwing a baseball toward home plate to start a play. The term comes from the Knickerbocker Rules. Originally, the ball had to be literally "pitched" underhand, as with pitching horseshoes. Overhead throwing was not allowed until 1884.

The biomechanics of pitching have been studied extensively. The phases of throwing include windup, early cocking, late cocking, early acceleration, late acceleration, deceleration, and follow-through.^[1]

Pitchers throw a variety of pitches, each of which has a slightly different velocity, trajectory, movement, hand position, wrist position and/or arm angle. These variations are introduced to confuse the batter in various ways, and ultimately aid the defensive team in getting the batter or baserunners out.

To obtain variety, and therefore enhance defensive baseball strategy, the pitcher manipulates the grip on the ball at the point of release. Variations in the grip cause the seams to "catch" the air differently, thereby changing the trajectory of the ball, making it harder for the batter to hit.

Starting pitchers typically throw over 100 pitches per game, while relievers throw fewer.^[2] The selection of which pitch to use can depend on a wide variety of situations such as; the type of hitter that is being faced, whether there are any base runners, how many outs have been made in the inning, or the current score, among others. The responsibility for selecting the type of pitch was traditionally made by the catcher by relaying hand signals to the pitcher, with the pitcher having the option to ask for another selection, however, current form is to have the manager or a coach relay the pitch selection to the catcher, via secret hand signals to prevent the opposing team from having the advantage of knowing what the next pitch will be.

Contents 1 Fastballs 2 Breaking balls 3 Changeups 4 Others 5 References

[edit] Fastballs

The fastball is the most common pitch in baseball, and most pitchers have some form of a fastball in their arsenal. It is basically a pitch thrown very fast, generally as hard as a given pitcher can throw while maintaining control. Some variations involve movement or breaking action, some do not and are simply straight, high-speed pitches. The cut fastball, split-finger fastball and forkball are variations on the fastball with extra movement, which are sometimes called sinking-fastballs because of the trajectories. The most common fastball type pitches are:

• Four-seam fastball
• Two-seam fastball
• Cutter
• Split-finger fastball
  • Forkball
  • Fosh
• Sinker

[edit] Breaking balls

Well-thrown breaking balls have movement, usually sideways or downward. The notion of a pitched ball's trajectory moving is actually incorrect; a ball "moves" due to the changes in the pressure of the air surrounding the ball as a result of the kind of pitch thrown. Therefore, the ball keeps "moving" in the path of least resistance, which constantly changes. For example, the spin from a properly thrown slider (thrown by a right-handed pitcher) results in lower air pressure on the pitcher's left side, resulting in the ball "sliding" to the left (from the pitcher's perspective). The goal is usually to make the ball difficult to hit or confusing to batters. Most breaking balls are considered off-speed pitches. The most common breaking pitches are:

• Curveball
• Knuckle curve
  • Slurve
• Slider
• Screwball
• 12-6 curve

[edit] Changeups

The changeup is the staple off-speed pitch, usually thrown to look like a fastball but arriving much slower to the plate. Its reduced speed coupled with its deceptive delivery are meant to confuse the batter's timing.^[3] The most common changeups are:

• Straight change
• Palmball
• Circle changeup

[edit] Others

Other pitches which are or have been used in baseball are:

• Knuckleball
• Eephus pitch
• Spitball
• Gyroball
• Shuuto
• Knuckle Slider

[edit] References

This article needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (January 2008)

v • d • e Baseball pitches Fastballs Four-seam · Two-seam · Cutter · Splitter · Sinker · Shuuto Breaking balls Curveball (12 to 6) · Knuckle curve · Knuckle slider · Slider · Slurve · Screwball Changeups Changeup · Palmball · Circle changeup · Forkball · Fosh · Gyroball Other pitches Knuckleball · Eephus pitch · Spitball · Yellow Hammer