Most teams draft and develop fast ball pitchers as starters. The understanding is that fast ball strike out pitchers (power pitchers) have better command of a game and can get more outs than pitchers who must rely upon speed changes or gimmick pitches.
The universal mechanics of pitching is gripping the ball with one's fingers on certain areas (on or off the seams) and in the release motion, torque one's wrist action to put more spin on the ball's rotation. Added spin creates more movement and at times the ball nose diving near the plate. The knuckleball toss is different. One does not throw the ball with wrist action, but "push" release it from the hand to allow nearly no spin on the ball. This creates a more erratic path towards the plate, as its velocity is less than a normal pitch.
Deception is the key to quality pitching. Most starters have three pitches; most relievers have a fastball and an "out" pitch. For starters, the fast ball is still the number one pitch (by percentage thrown). A starter than has an off-speed pitch (curve or change up) and a drop pitch (slider or sinker). How a catcher (manager or veteran pitcher) "calls" a game (the sequence of pitches to a batter) is the chess game between the teams.
It is a simplification used by many broadcasters that a pitcher is limited to his one or two types of pitches. In reality, a pitcher who may only throw a fast ball and a change up can effectively have more than just two weapons. First, a pitcher has a wind up to gather momentum for the release point of his pitch. His arm motion creates a "slot" toward the release point. Pitching coaches monitor slot position to determine whether a pitcher is having mechanical issues (which create control issues). A range of slot positions can be directly over the shoulder (for a 12-to-6 curve ball motion) down to a near underhand submarine style throw. There may be a dozen slot angles a pitcher can choose on any given pitch. However, pitching coaches train their players to keep one under the view that it is more important to have a consistent slot position to have consistent pitch location.
A pure fast ball pitcher could grip and throw the ball at the same speed, but create "three" different pitches by arm releases at the 3/4, side arm and submarine slots. Why would that be important? Because the batter is trying to pick up the ball as quickly as possible. A fraction of a second early increases the eye to hand coordination of the batter, which equates to more contact with the ball. A pitcher with multiple arm angles conceals the ball more from a batter's eye perspective.
The same fast ball pitcher with three arm angles can also add "three" more pitches to his arsenal. For each release point, he can be throwing with the seams or off the seams, which means the ball may have more spin or movement. A four seam fastball with velocity appears to rise to a batter, while a two seam fastball appears to have more movement to a batter.
Different pitching styles, from velocity, pitch type, movement and location are all the weapons a manager has at this disposal during a game, especially when managing bullpen match ups later in games.
Scouting batters has become a thick statistical report. With video on every game, and detailed at bat pitching location charting, every team has a break down of every batter's tendencies and weak spots. Teams chart batters into hitting zones.
The batting zone grid is simple from the strike zone of letters to knees: instead, middle and outside crossed by high, center and low. Every batter has a sweet spot, the zone where he sees the ball the best and has most contact (hits). There are also dead zones where the batter has a difficult time handling pitches in that area. Hot and cold zones are a reflection of various factors, including batting stance, eye lines to the pitcher, and the mechanics of the swing (from loopy, choppy, fluid, or drop contact.) A recent trend has been that many power hitters prefer low balls, and they drop the bat down and "golf" balls out of the park.
A batter knows his own weak spots. He goes up to the plate looking for pitches in his hot zones. He is also looking for pitches to foul off in his weak zones. Even though the average major league hitter is batting only .250, plate management and waiting for a pitcher to "make a mistake" and groove one into the batter's personal hitting zone, can make an average hitter into a .300 hitter.
In many respects, it does not matter what speed a pitch lands within a zone, it is more important if it a hot or cold zone for the batter to make contact. In order to "entice" outs, a pitcher will set up a batter with a series of pitches. One approach is "going up the ladder," throwing consecutive fast balls first low, middle and high. Another approach is to throw pitches in a location to create a result. Throwing a ball outside to a pull hitter will produce a ground ball.
So the cat and mouse game is between pitcher and batter. The one advantage is to the pitcher, who knows in advance what he will be throwing to home.
Back to the fastball pitcher in our example. Even if the coaches have him in a single arm slot release, he still has a dozen locations in which to throw the ball: he nine zones within the strike zone chart, plus high, outside and in the dirt outside the strike zone.
Many pitchers have a fear of throwing pitches within the strike zone. They are nibblers: they want to have their pitches nip around the inside or outside corners of the plate. But that philosophy turns a pitcher's advantage into a batter's advantage since the hitter now can concentrate on three or four locations instead of the dozen possible areas. There are also throwers; they rely on the type of pitches more than control. Marmol is a classic example of that: he throws a slider or a fastball, and where they wind up, nobody knows. Then there are the outsiders, pitchers who refuse to pitch inside to batters because they don't believe they can control their pitches well enough so they won't drift to the middle of the plate and be easy hits. But by not throwing inside, these pitchers effectively take away half of the pitching zones available to them. (Most batters have difficulty with inside pitches. They cannot extend quickly enough to get full power on their swings.)
An excellent training method to increase pitching zone control would be to have a cage above home plate the size of a hitting strike zone with nine nets sewn together to catch pitches. A coach would stand beside the pitcher and call out the location. Once the pitcher gets used to throwing called locations at the cage, the coach then use actual hitting charts to simulate a game situation. This could train the pitcher on how to attack an opponent by using pitching zones instead of just relying on the types of his pitches. Example, the hitter's chart shows a cross: he hits all middle and across the belt boxes. A pitching coach could train the pitcher to attack this hitter as follows: inside high, inside low, outside high, inside middle, outside low. A pitcher learns to tempt a hitter near one of his hitting zones in order to set him up for the third strike in a zone outside the hitter's comfort level.
Deception in delivery and location of pitches are the most effective weapons of a pitcher.
