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Revisit the third and final part of Kevin's scouting vocabulary primer, which covered the qualities evaluated when a scout looks at each of a pitching prospect's offerings. The piece was originally published as a Future Shock column on March 16, 2006.

Scouting pitchers is generally a more difficult proposition than evaluating position players. With young pitchers, scouts are required to place that much more of their projection on their anticipation of a player's future, leaving more room for error. Because of the built-in risk for failure, either through injury or lack of performance, more pitchers are drafted than needed, and therefore an inordinate amount of the scouting budget is spent on hurlers, in order to have just a few reach the big leagues. While the average team carries 11 or 12 pitchers on their active rosters, a full 55% of the first 100 picks in the last two drafts have been pitchers, so the failure rate is higher.

The Scouting Scale Returns:

The 20-80 scale is also used for pitchers, only this time, individual pitches are graded. Over the last two days I used Joe Ballplayer as our example, so today let's take a look at our top high school draft pick, Tommy Throwhard.

Fastball Velocity      60        70
Fastball Movement      40        50
Curve                  --        --
Slider                 45        60
Changeup               30        45
Other                  --        --
Control                35        50
Command                40        50

Young fresh raw arms, on sale this week at Target! Without even going into a full explanation of each category, we can see a few things here about Tommy. Tommy throws hard. Tommy already has a pretty good breaking ball with plenty of promise. Tommy has just two good pitches, and has problems throwing strikes with his power stuff.

Now let's look at how each pitch is graded:


In the scouting report for Tommy above, I split the fastball grade by velocity and command. Some organizations do this, but some do not. For those that don't, the score for a fastball is a combination of velocity, command and movement. For velocity only, the score is generated by the radar gun and the radar gun alone. Average (50) velocity is generally 89-91 mph. An 80 velocity score is 97+ mph, while anything in the mid-80s or below gets you into the 30s and 20s. It's important to note that difference between "sit" and "touch" when it comes to velocity. If you go see Matt Cain this year, and sit behind home plate with a radar gun, his first 10 fastballs might end up something like this:

93, 92, 95, 94, 91, 98, 92, 92, 95, 93

So Cain is sitting at 92-95 mph, but touching 98. Obviously, one would measure far more than 10 pitches to evaluate a pitcher, but you get the idea. The velocity score is based on where a pitcher's fastball sits at consistently, not what he can reach back for when he needs to dial it up a bit.

A quick note about southpaws: Lefthanders make up what is generally believed to be 10-12% of the general population, but made up 27.8% of the 2005 major league pitching population (thanks to Thom Henninger of STATS, LLC for the data). So the chances of your left-handed kid making it to the show are roughly three times that of a righthander. Because of this, the pool of lefthanders is logically weaker. Finding righties who throw 92-94 isn't very hard. Finding lefties that throw that hard is quite difficult.

Fastball Movement:

There are two basic kinds of fastballs: a four-seam fastball and a two-seam fastball. Some pitchers throw just one, some throw both, and some even throw variations of the two-seam that qualify as other pitches.

The four-seam fastball is the true heater, or cheese, or cheddar, or gas, or whatever other charming term you'd like to use. Gripped across the seams, this is the pitch that gets the most velocity and the least movement. That said, all pitches need to have some movement to be effective. Even a 100 mph fastball thrown straight as an arrow is a hittable pitch in the major leagues. Most pitchers try to alter their grip somewhat to give the ball some tailing action that moves the pitch slightly in or away from opposing hitters, while others get maximum backwards rotation on the pitch in order for it to ride to home plate on a higher trajectory.

Two-seam fastballs are still fastballs, but ones in which some velocity is sacrificed for movement. The pitch is gripped with the index and middle finger along the two seams, with more or less pressure being applied with one of the fingers to spin the ball in a way that provides break. Things can get a little confusing with two-seamers, as some variations of the pitch are different enough to earn their own monikers. A good two-seam fastball can be termed a sinker because it has strong downward break, and pitchers who can add horizontal break as well are throwing a cutter. Another variation on this pitch is a splitter, in which the two gripping fingers are widened to get serious downhill break.

When judging fastball movement, scouts are looking for both the "natural movement" in a player's four-seamer and the more specifically-generated movement is his two-seamer.

Some Prospects With Very Good Fastballs:

Velocity Only: Juan MorilloFelipe PaulinoJoel Zumaya Overall Fastball (Velocity, Command and Movement): Matt CainFrancisco LirianoJustin Verlander


A curveball has a special grip, and is thrown with a snap of the wrist at the pitch's release so that the ball has forward rotation, as opposed to a fastball's backwards spin. This causes the pitch to break down towards the plate at a much greater rate. In addition, a good curve ball is released more off of one finger than the other, giving the pitch horizontal spin as well. Without getting into the somewhat complicated physics of a spinning three-dimensional object through a resistant force (in this case, the air), this spin makes a curveball, well, curve. Nothing about a curve is an optical illusion. A curve has a stronger downward break than a fastball or slider because of the forwards spin and the fact that it is thrown with less velocity (generally in the mid-70s), makes it more susceptible to the forces of gravity. Because of the diagonal spin, the pitch really does move both across the plate and downwards in a manner that physics professors would call quadratic, but scouts would call "with late break." As a general rule, 75% of a curveball's break occurs in the last 50% of the pitch's time in the air. So a good curve ball is one that drops off the table, and moves across the plate with late break. A curveball that doesn't have enough forward spin will not break down as sharply, and will therefore "hang." When talking about curveballs, scouts will often talk about "tight" or "biting" rotation for a curveball that breaks strongly down.

Some pitchers also throw a knuckle-curve, but this is a misnomer, as obviously a pitch has to spin (unlike a knuckler) to break. The knuckle-curve (also referred to as a spike curve) is a harder-thrown curve ball with a different grip, where one finger is bent back (therefore gripping the ball on the knuckle) to provide the spin.

There are very few out there, but some pitchers throw a screwball, which is basically a reversed curveball, in that one delivered from a righthander will break in on a right-handed hitter. To throw such a pitch requires a violent delivery that strains both the shoulder and elbow, and it's not a pitch that any pitching coaches that I know of teach at the professional level.

Some Prospects With Very Good CurveballsGio GonzalezRich Hill


In simplest terms, the slider is somewhere between a fastball and a curve. Generally thrown in the mid-80s, the pitch has more velocity than a curveball, and therefore less downward break, but more horizontal break as it sweeps across the plate. The pitch requires significant feel; for a slider to be graded as a plus pitch (60 or higher), it must contain "two-plane break"–that is, it must break right-to-left (or vice-versa) while also breaking down. When a pitcher throws a slider too hard, it tends to only go across the plate, but not down. This is called a flat slider, and it is the slider's equivalent to the hanging curve.

A note on velocity and break: some scouts have a continuum of pitching based on velocity and break that goes something like this:

<--Most Break------------------Least Break-->
Curve   Slurve    Slider    Cutter   4-Seamer
<--Least Velocity------------Most Velocity-->

The Slurve is a pitch that falls somewhere between a slider and a curve, and it's generally considered a bad thing. A good slider is effective because it's thrown hard enough to look at first like a fastball, but the breaking aspect fools hitters. A good curve ball is effective because of the amount it breaks. A slurve is an ugly stepchild in that it's not thrown hard enough to look like a fastball, and it doesn't break enough to fool hitters. Often you'll hear about amateur talent having a "slurvy" breaking pitch. For those players, the pitching coaches when they enter the pros will study the player and determine if the pitcher should focus on adding velocity (throwing a true slider), or adding break (throwing a true curveball) based on the pitcher's abilities.

Some Prospects With Very Good SlidersJonathan BroxtonCraig Hansen


An effective change-up is often the difference between a slot in the rotation and a job in the bullpen. A change-up is basically a pitch thrown much more slowly than a fastball (in the 70s is ideal), but is all about deception, as the pitcher attempts to deliver the pitch with the same arm-action as that of his fastball. Very few pitchers enter pro baseball with a good change-up, and virtually no high school pitchers do (they easily dominate prep hitters with their velocity, so there is never any need for one). A good change will be thrown with a pitching arm moving at the same speed as he uses for his fastball, while a modified grip provides reduced velocity and some snap on the release provides break. It is a pitch that usually is taught to pitchers at the lower levels, and it often takes a long time for a pitcher to become effective with it, if they ever do.

Some Prospects With Very Good ChangeupsCole HamelsChuck James

Bring It All Together:

Much like the scouting report for position players, a scouting report for pitchers will also contain a plethora of information beyond just the 20-80 scores. Other than the information mentioned when I discussed Joe Ballplayer's scouting report, a pitcher's scouting report will have a number of lengthy notes about a pitcher's mechanics. Arm slot is noted individually; most scouts prefer an overhand delivery, as the � arm slot often leaves a pitcher more susceptible to their opposite side. As I mentioned in the State of the Systems for the AL WestJered Weaver could become the poster boy for this issue.

Pitching mechanics are much like hitting mechanics in that most are doing the same basic thing, yet each is highly individualistic. They're a complicated subject, and I even know this one guy who wrote a book about it. When looking at a pitcher's delivery, scouts want to see mechanics that are simple, effortless, and repeatable. They do not want to see something with a lot of moving parts. They want to see a delivery that looks natural and fluid. Pitchers who don't have this are often described as having a violent or max-effort delivery. They want to see a consistent release point, where the arm is at the same angle on every pitch delivered, as inconsistent release points mean control problems.

Scouts are also looking for parts of the delivery that can be a pretense to injury. The three most-common danger signs are:

  • Throwing across the body: this puts undue strain on the shoulder.
  • Over-snapping the breaking ball: this puts undue strain on the elbow.
  • An unbalance landing where the foot is offline, and the pitcher is falling to one side: This can strain both joints.

With all of this, pitchers still get injured. Mark Prior has been used as a model of ideal mechanics in the past, and we all know how well that has turned out so far.

Body-type is also important. Scouts do have an ideal body-type they are looking for with power pitchers, and it's generally 6'2" to 6'5" and a little on the meaty side, say 210-240 pounds. Think Roger Clemens. Taller pitchers tend to have a problem with a consistent release point, while shorter pitchers (who logically have shorter arms) have a problem getting a good downward plane on the ball.

When a scout adds up a pitcher's abilities, mechanics and body, they often will put in a final projection for the pitcher's role, be it a No. 1 through No. 5 starter, a reliever, or a closer. To be considered a potential No. 1 pitcher is extremely rare. In the world of scouting, the term No. 1 is not relative. While there are 30 teams in baseball, there is nowhere close to that number of No. 1 starters, and there are far fewer than 60 No. 1 and No. 2 starters. To be projected as a No. 1 starter, you are looking for a pitcher who can deliver 225 innings with an ERA under three. In 2005, there were only 13 pitchers who threw 225 innings or more, and only four of those posted a sub-3.00 ERA. Pitchers who project as No. 1 starters have a durable body, and more importantly, excellent stuff. By that, I mean that a No. 1 has two "out pitches," or pitches that he can use at any time in the count to generate swings and misses. That combination is a rarity, but he must also have a good change-up and throw strikes. At the other end of the starting spectrum, a No. 5 guy simply has at least three usable pitches, some durability and decent command.

Pitchers who have just two pitches are generally relegated to the bullpen. Most often, the two-pitch combination is fastball/breaking ball, but there are some pitchers who go fastball/changeup because of their inability to develop a good breaking pitch. Many pitchers who have questionable mechanics are also moved to the bullpen, as their violent deliveries are less dangerous to their long-term health when they are only throwing 20 pitches in a game. Makeup is also an essential part of projecting pitchers, but that's a subject that deserves a much lengthier discussion than can be provided here. As much as some people talk about closing being more of a matter of opportunity than anything else, that's simply not true. Closing takes a special kind of makeup, be it a nasty one or an unflappable one.


Outliers exist in any situation, and pitching is no different. For example, Mariano Rivera is a one-pitch closer, but that pitch (an 80 cutter) is so good it doesn't matter that hitters know it's coming. The other type of outlier can only be described as Jamie Moyer. What it takes to succeed in the majors and what it takes to succeed in the minors can be different. Lefthanders who can throw strikes and spin a breaking ball often put up excellent numbers in the minors, but their lack of a true out pitch leaves them unprojectable. Unfortunately, when a person who writes about prospects says something disparaging about these players, people inevitably bring up Jamie Moyer. Like Rivera, Moyer is his own type of outlier. Every system in baseball has three or four lefties with Jamie Moyer's stuff, but there's only one Jamie Moyer. As a basic rule, always go with the power stuff.

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