http://www.hardballtimes.com/main Baseball. Insight. Daily. en studes@hardballtimes.com Copyright 2013 2013-05-24T08:08:15+00:00 http://www.hardballtimes.com/main/article/nuts-and-bolts-of-hitting-in-the-big-leagues-with-morgan-ensberg/ http://www.hardballtimes.com/main/article/nuts-and-bolts-of-hitting-in-the-big-leagues-with-morgan-ensberg/#When:08:02:15
I’m sorry to say that most of the time these interviews leave me mildly disappointed. They never ask questions about things I want to know about. Well, I finally decided to do something about it.

Morgan Ensberg, former right-handed hitting third baseman for the Houston Astros, was kind enough to allow me to interview him, and I finally had the opportunity to ask all those questions I’ve been dying to ask.

Matt Lentzner: There seems to be two basic approaches to hitting. There are the "see the ball, hit the ball" types that go on pure reactions and those that "guess" and try to anticipate what the pitcher will throw. Which type of hitter were you?

Morgan Ensberg: I was a see it and hit it. But when I was going really badly, I changed into a guess hitter and that was not the correct move. It would have been better to just attack. Of course that is hindsight.

ML: Could you elaborate on how trying to guess on pitches was a bad thing for you?

ME: Guess hitting was bad for me because I never guessed correctly.

ML: There are also two types of swing philosophies. There's the Ted Williams back-hand, rotational approach and the Lau front-hand, translational approach. Did you subscribe to either of these?

ME: My swing is probably more Williams. My right hand was very dominant in my swing.

ML: Can you describe how being a back-hand dominant hitter affected your hitting style?

ME: By having a dominant right hand, it caused me to "roll over" on balls that I needed to stay through on. Basically, my bat will be coming out of the zone early and it will cause me to go get it out in front of the plate which causes hooking.

ML: Where on the pitched baseball did you aim? Did you try to hit it center-of-mass or did you aim higher or lower than that?[1]

ME: I just tried to hit the ball. I didn't say above or below. Just hit it.

ML: Did you ever see a "dot" on a pitch and if so, which pitches did you see it on? What other, if any, visual clues were you able to pick up from a pitched baseball?

ME: I saw dots on sliders all the time. I could see seams tumble on changes. We see everything.

ML: Was you ability to identify pitches affected by where the pitch was located? For example was it easier to see a pitch that was low or high? Was it easier to see a pitch that was inside or outside?

ME: It is easier to see pitches that are high and inside because of proximity to your eyes.

ML: How did the handedness of the pitcher affect you ability to identify his pitch? Many batters claim that a pitch from a same-handed pitcher is harder to "see." Can you explain why?

ME: It isn't that the same side is hard to see, it is that off-speed pitches start at you. Against a lefty, you don't have any ball coming at you.

ML: How often were you fooled by a pitch?

ME: You are fooled a lot. If the ball moves just an inch from where you think it is going to be, you will hit the ball softly or just miss it entirely.

ML: How often does a typical MLB pitcher tip his pitches and how much of your hitting "game" involved picking up "tells" from a pitcher?

ME: I saw a guy tipping his pitches once. I struck out swinging as hard as I could at three balls at my chin.

ML: How much situational hitting did you do? Most hitters change their approach when they have two strikes. What did you do with your approach to improve your results with two strikes? Did you try to hit behind the runner with a man on second? How is that accomplished? Are there any other situations that deserve mention?

ME: I already hit choked up, but I would take another half inch. With two strikes I would get my front foot down very early and I wouldn't move it. I tried not to move my body and just use hands.

I always tried to hit the ball on the ground to right with a man on second and no outs.

With the bases loaded and no outs you are never allowed to strike out. Of course I did, but your thought process is to get a run across.

With a man on third and less that two outs I would try and get the ball up in the zone unless the infield was back, in which case I looked to hit a ground ball in the middle of the field.

ML: Since you didn't aim for spots on the ball, how did you purposefully hit a ball on the ground? Was it just a question of looking for a low pitch to swing at?

ME: When you try and hit the ball on the ground, you focus on the barrel of your bat and not the ball. Of course you will hit the top of the ball, but the focus is on your barrel.

ML: Did you ever try to hit a home run? Say it was the bottom of the ninth of a tie game and the count was 2-0, would you be looking to hit a homer on the next pitch?

ME: I have never tried to hit a home run in my life. I don't know what I would even do to do that.

ML: When you were hitting against a pitcher you had never faced before how did you approach that?

ME: I would just make sure I knew what pitches he threw and the speed of the fastball. We always had a video playing in the clubhouse before the game that would show his last start. But, when in doubt I would want to attack.

ML: How did knowing the speed of their fastball affect your approach?

ME: If a pitcher throws 100 mph then you know that he is probably a fastball pitcher and you have to gear up for that.

ML: In 2006, the year after your All-Star year you had more walks than hits - a pretty unusual stat in baseball. Why do you think this happened? Did pitchers stop challenging you in the strikezone after your 36-home run season?

ME: Those pitchers didn't have to pitch to me at all. They just said I'll try and hit a corner and if I miss then I'll face the next batter.

ML: How often did you play at less than 100 percent due to fatigue or nagging injuries?

ME: The last time any player was 100 percent they were 12 years old.

ML: Just wanted to sneak in a fielding question since it's something we've argued about on Tom Tango's blog. Based on his analysis of the difficulty of fielding positions, he has second base and third base being equal in difficulty. I agree with that conceptually, but I feel that those two positions have vastly different requirements. Can you comment of what skills a third baseman needs and how that compares with a second baseman?

ME: Second base is much easier than third base. You can base the majority of that on the throw and having to read bunts. I am not saying that because I played third; I am just saying that there is less "reading" at second.

Click here to learn about THT's download subscriptions.]]> Matt Lentzner 2010-04-12T08:02:15+00:00 http://www.hardballtimes.com/main/article/a-pitching-model-playing-the-slots1/ http://www.hardballtimes.com/main/article/a-pitching-model-playing-the-slots1/#When:06:44:15 Chad Bradford and Brad Ziegler don’t hold the ball any differently than any conventional pitcher. The only difference is their arm slot.

But before we get too far into that topic, we need to understand how different pitches are spinning the ball and what kinds of pitches result. As in my other articles, it is instructive to create a somewhat artificial construction to help visualize what is going on. Let us consider a pitcher who throws perfectly overhand. His arm slot is perfectly perpendicular to the ground when he throws. There are pitchers with very high arm slots such as Hideki Okajima, a relief pitcher with the Red Sox. High arm slots are reputed to provide more velocity, less lateral movement, and short careers due to extra strain on the shoulder. I don’t have any easy explanations for the velocity boost nor the mistreated shoulder, but I can shed some light on why these guys have a reputation for less movement.



Here’s a typical Okajima delivery. He is one of the most extreme overhand pitcher in the major leagues. And Yes, he’s not looking where he throws when he pitches.

Let’s look at how a standard fastball would look from a right-handed extreme overhand pitcher from the batter’s perspective. Because the arm slot is perpendicular to the ground, a fastball, with the most efficient “inline” spin has a spin axis perfectly parallel to the ground and perpendicular to the arm slot.



Notice how it has pure backspin. That is, pure hop with no tailing or boring movement whatsoever: a straight pitch.

Now let’s look at an overhand curve—the opposite of a fastball—from the same pitcher and the same point of view.



Notice how this pitch is also perfectly aligned except the spin is all topspin. This pitch is also straight, but where the fastball hops, it dives into the dirt.
There you go. Two bread and butter pitches that an overhand pitcher could throw and neither moves in the horizontal plane. Their reputation of lacking movement is definitely deserved.

Let’s move onto our next hypothetical pitcher: the perfect sidearmer. Sidearmers have a reputation for less velocity, a lot of lateral movement, and a more shoulder friendly delivery. In fact, as Pedro Martinez’s shoulder gets more and more damaged the lower his arm slot gets. But once again, I can only shed light on the side to side movement that is observed.

Here’s the fastball from a right-handed sidearm pitcher from the batter’s point of view.



Pretty weird, I know. There’s no backspin at all. Is that even a fastball? It’s held like one, for sure. All that has happened is that the arm slot has tilted 90 degrees so the spin axis also tilts 90 degrees. What you end up with is a fastball with tons of action and tons of sink since there is no backspin to give it any hop.

You probably have a good idea what the curveball looks like, but here it is anyway.



Now we end up with a curve with no down-bite. It still has the speed of a curve and will get some drop by virtue of gravity, but all the movement induced by the spin is to the side. It will have a lot of sweeping movement away from a same handed batter. The point of all this is to establish the idea that all that happens with different arm slots is that the spin axis of the pitch changes. If you’re with me so far let’s continue.

We’re going to return to our extreme overhand righty pitcher in the Okajima mold. Here’s a progression of pitches as seen by the batter from one end of the spectrum to the other. We’re marking 45 degree intervals as we go. I’ve named them with roughly the popular names we recognize them by. A pitching coach might quibble with the exactness of my names, but for our purposes they are close enough.

Overhand right-handed delivery as seen by batter


It’s worth noting that once you move away from the extremes of fastball and curveball you start to see some misalignment with the spin that is most evident with the middle pitch, the slider. In fact this football-like or bullet-like spin doesn’t contribute anything to the movement of the pitch. It actually decreases the effect of the spin. If a pitcher threw a pitch with perfect bullet spin it would not move at all—no hop, no dive, no slide, nothing. So a slider is actually an inefficient pitch spin-wise, although this inefficiency in no way lessens its effectiveness. I’ll go into this in more detail in a future article, but suffice to say, when you have off-kilter spin the direction of the movement doesn’t change; it just gets reduced somewhat. Also, this off-kilter spin is the source of the dot that some batters with especially keen eyesight sometimes observe on cutters, sliders, and slurves. The dot forms because there’s a dark colored (red in relation to the white ball) seam at the axis of spin and it is tilted into a position where it is visible to the batter.

Now that this little sidebar is out of the way, let’s look at the same progression from a sidearmer.

Sidearm right-handed delivery as seen by batter


Make sense? But what are those intermediate pitches, the cutter, slider, and slurve doing exactly? It’s easy to get confused so let’s look at a Rosetta stone of sorts that can translate pitch movement into terms we can understand. The names correspond to how pitches move from a conventional “high ¾” arm slot.



So by matching up the pitch movement with this key we can see that a sidearmer’s fastball moves like a screwball, his cutter moves like a sinker, his slider like a fastball, his slurve like a cutter, and his curveball like a slider. This is why these odd birds of the pitching world can be so successful even without the levels of raw talent other conventional pitchers have. They have a completely different array of pitches than a conventional pitcher, and because they are rare, batters are not familiar with what kinds of pitches they will see. When a batter has to face submariner Brad Ziegler, whose fastball acts like 90 mph screwball from a conventional pitcher, it’s easy to see why they have so much trouble.

Here’s the big chart with four different arm slots and the progression of five pitches we have already been discussing plus the sinker, which is a lot like a cutter except with movement in the opposite direction.
For the purposes of this chart, the slots as described have the following “clock” angles.
1. Overhand: 12:00
2. Three-Quarter: 1:30
3. Sidearm: 3:00
4. Submarine: 4:30

I’ll leave it at that with the one parting comment that I already mentioned at the beginning of this article: the most common arm slot is the “high ¾”. Most pitchers will fall somewhere in between the overhand and ¾ arm slot.
I’d like to thank former major league pitcher and sidearmer Dave Baldwin. He was invaluable in providing some real-world sensibility to the many revisions this article went through.

Overhand right-handed delivery as seen by batter


Three-quarter right-handed delivery as seen by batter


Sidearm right-handed delivery as seen by batter


Submarine right-handed delivery as seen by batter



Click here to learn about THT's download subscriptions.]]> Matt Lentzner 2008-11-13T06:44:15+00:00 http://www.hardballtimes.com/main/article/a-mechanical-model-of-pitching/ http://www.hardballtimes.com/main/article/a-mechanical-model-of-pitching/#When:05:05:15 -Albert Einstein

That’s a well-worn quote from a very famous physicist, but it is appropriate with regards to this article. I’m going to lay out a model of how pitches are thrown and try to keep it as simple as possible without being too simple. In a way my first article, Why Grounders go one Way and Flies go the Other was about the same thing. The model people had been using for hit balls was too simple and some important details were lost.

Let’s start out with a very simple model of pitching that I will tell you up front is too simple. It’s worth setting up the straw man since tearing him apart will be instructive. The exercise will naturally lead us to the more sophisticated model that is just complex enough to explain what is going on and simple enough to understand.

I think it is common for people to think of pitching as a simple arm that rotates at a certain speed and releases that ball at a certain point so that it flies toward the strike zone. Here’s a little cartoon of what that would look like in three steps:



We start with the arm cocked back and the fingers holding the ball. As the arm accelerates forward, the fingers open at the correct point and release the ball. The ball flies off toward the strike zone and the arm continues to rotate and decelerate. It’s a simple machine that turns rotational momentum into straight line momentum.

Not surprisingly, there are a lot of problems with this model. First of all, how does a pitcher impart spin on the ball? We know that almost all pitches are thrown with spin with the notable and rare exception of the knuckleball. This model shows no mechanism for spin to happen. We have all seen fastballs hop and curves curve, and we know that this is caused by a lot of spin put on the ball when it is thrown. Somehow, from the time the ball is in the pitcher’s hand to the time it is thrown, the ball acquires spin. We know it’s not spinning while he is holding it, but we also know it is spinning once it has been thrown. This model offers no help in explaining this.

There’s also a less obvious problem that really sinks this model for good. Really good pitchers can throw all their pitches with the same arm speed. That’s what makes a good changeup so deceptive. The pitcher does everything the same, but the ball leaves his hand eight to 10 mph slower. That’s a pretty mysterious ability and is not reflected in the simple model we’ve kicked around so far.

The model has no elbow or wrist, but that’s not the key piece that is missing. The real problem is the fingers. A pitcher’s fingers do a lot more than simply release the ball, as we will see. Let’s throw this model away and look at how a fastball is really thrown.

Contrary to what you might think, there are actually two points of release when a pitcher throws a fastball. First it leaves his hand and then, a split second later, it leaves his fingertips. This two step process, happening in the time it takes a ball moving in excess of 80 mph over the space of a few inches, makes all the difference in the world. It allows the fingers to keep adding energy from the arm and wrist even after the hand has released it. This action typically adds about 7 mph to a thrown fastball’s speed.

When a scout says the ball explodes out of a pitcher’s hand it is more than just colorful scout-speak. A fastball really does pick up speed as it is released.
At the same time, the ball also picks up backspin because the force applied at the fingertips is not in alignment with the flight path of the baseball. Some of the energy goes into increasing the speed and some goes into spinning the ball which gives the fastball its hop.
Here’s another threesome of illustrations that shows what I am talking about:



The first picture on the left shows the fastball just as its leaving the pitcher’s hand. At this moment the hand and the ball are moving at the same speed, but their paths begin to diverge as the hand follows an arc and the ball travels straight. A few moments later the ball reaches the fingertips and further force is applied to the ball, but since the ball and hand (one travelling straight and the other in an arc) are no longer going in the same direction. The fingertip force is applied in a direction that is out of line with the path of the ball.
This does two things:
1. Adds velocity to the ball (The part of the force that is in line with the path of the ball)
2. Adds spin to the ball (The part of the force that is perpendicular to the path of the ball)

The last frame just shows the results of this action. The fingers follow through and the ball heads off with a speed boost and a lot of backspin.
All fine and dandy, but how does a pitcher throw a fastball at 90 mph, a cutter at 88 mph, a slider at 83 mph, a changeup at 81 mph, and a curveball at 77 mph, all with the same arm speed? It’s all about applying inefficiencies to the hand action.

To throw a cutter the pitcher simply holds the ball off center. Let’s take a look at the cutter from a top view compared to a fastball on the left and a cutter on the right.



By holding the ball a little off-center the pitcher changes how the force is applied to the baseball. The spin axis is no longer perpendicular to the direction of travel of the baseball so it has cutting action instead of the hop of a traditional four seam fastball. Another effect is that now the pitcher can’t push on the ball as efficiently as he could with the fastball because of the misalignment of the fingers and the hand action. That explains the modest loss of speed for the pitch. A sinker is similar to a cutter, but the misalignment happens on the other side of the ball and causes movement in the opposite direction.

A slider isn’t much different in kind from a cutter. It’s just a matter of degree. With a slider the fingers end up all the way on the side of the ball. The resulting spin resembles a football spiral more than a variety of fastball. This maximizes the side to side movement, and further erodes the efficiency of the pitching motion. Because of this radical misalignment, almost no energy from the fingers can be applied to the path of the ball and it ends up going about the same speed as the hand speed. There’s a lot of variation among sliders, but a garden variety slider will clock in at about 83mph.

How about changups then? It’s no accident that the slider and changeup are similar in speed even though the mechanism of how the pitch is thrown is very different. With a changeup the pitcher deliberately holds the ball deeper in his hand, killing the finger extension and letting the ball roll off his fingers instead tapping into the arm and wrist rotation and driving it like he would with a fastball.



The ball leaves his hand slower than the arm speed, usually about 2 mph although pitchers such as Trevor Hoffman and Johan Santana can subtract significantly more speed than that. By letting the ball roll off the finger tips instead of driving it, the pitcher adds no speed with his fingers and actually reduces the speed of the pitch. Some of that forward momentum the ball has at release is converted into backspin which further reduces the pitch speed.

To wrap things up let’s look at the curveball. Although the grip is completely different, in many ways it resembles a changeup. With the fingers positioned in front of the ball there is no way for the pitcher to use his fingers to add speed to the ball. In fact, the only thing he can do is exchange velocity for spin. Also, with the ball choked so far down in the hand it reduces the amount of speed at release since the mechanical advantage of the arm length is reduced several inches and this subtracts about 4 mph to the speed of the ball at release. That is why a curve is one of the slowest pitches a pitcher will throw—typically 13 mph slower than his fastball. The ball might leave his hand at 79 mph and then he will steal an additional 2 mph and convert it to topspin ending up with a 77mph curve that, due to topspin and reduced speed, takes a sharp dive as it reaches the plate and is very difficult to hit.

The model shows that it is impossible for a pitcher to throw a curveball faster than a slider. In fact, where baseball lore describes discrete pitches, there are actually a continuum of pitches that are available. The only rule is that the fastball is the most efficient pitch and the more you drift away from the pure backspin of a fastball the more speed you sacrifice. A pitch that is somewhere between a curve and a slider, known as a slurve, will be thrown at a speed somewhere between a curve and a slider.

Of course a pitcher could deliberately slow his arm down to get a better speed differential, but this is counterproductive. Changing arm speeds means tipping your pitches. Professional batters pick up on this stuff. If they know what’s coming, you won’t be pitching in the major leagues. A consistent arm speed is what every pitcher aspires to.

Besides getting a really good handle on how grips and pitching works in a physical sense, we can also use this model to decipher some baseball phenomena that didn’t make sense before. Have you ever heard a coach or scout complain that a pitcher was “overthrowing” his fastball? It always puzzled me. Wouldn’t you want to throw the fastball as fast as possible? Overthrowing is throwing the ball harder yet straighter. Major league hitters can generally catch up to even an exceptionally fast pitch. If it’s not moving much they will hit it on the screws more often than not. The movement that a fastball has is very important—it’s more than just about the speed.

Looking at the model we can see that a pitcher could theoretically use his fingers in such a way as to apply more of his force budget to accelerating the ball and less to spinning it. Voila, an overthrown fastball: faster, but with less movement. Likewise, a pitcher could theoretically do the opposite and apply too much spin while sacrificing speed. I’m sure there’s a happy medium. The more elements a batter has to worry about the better so keeping him worrying about the speed and the movement is the best approach.

Just to wrap up I’d just like to say that our first model that we thoroughly bashed is not totally useless. It does describe how a knuckleball is thrown quite nicely. In part two of this article, A Pitching Model: Playing the Slots, we will look at arm slots and how they affect a pitched ball.


Click here to learn about THT's download subscriptions.]]> Matt Lentzner 2008-10-30T05:05:15+00:00 http://www.hardballtimes.com/main/article/why-flies-go-one-way-and-grounders-go-the-other/ http://www.hardballtimes.com/main/article/why-flies-go-one-way-and-grounders-go-the-other/#When:04:03:15
In his book, "The Physics of Baseball," Robert Adair theorizes on this subject. His explanation in a nutshell is that when hitters are out in front of a pitch they tend to hit it into the ground, and when they are behind a pitch they tend to hit it into the air. The fact that the bat does not move in the same plane as the ball caused this effect.

There may be some truth to this theory, but I think it is overwhelmed by the simple geometries involved when a cylindrical bat collides with a spherical ball. Just by looking at the results of this collision we will see how grounders will tend more to the pull field and flies to the opposite field. It doesn’t matter who’s swinging the bat or how good or bad the hitter's timing was.

To get to the nitty-gritty of this problem, we need to make some assumptions. While not 100% accurate, they get us close—physicists do this all the time to make their lives easier. We can do this because we are not trying to get an exact answer, but rather demonstrate the principle.

1. The bat is a perfect cylinder and the ball is a smooth, perfect sphere. This isn’t too far out. The business end of the bat is very close to a cylinder, and a ball without stitches would be very close to a sphere.

2. The ball does not contribute to the outcome. Because the bat is much more massive than the ball, it contributes about 80% of the effect. We’ll pretend that the last 20% doesn’t exist. We’ll be in the ballpark, so to speak.

3. The ball travels on a straight line from the center of the pitcher’s mound to the center of home plate and the bat strikes the ball perpendicular to this line of travel. Pitchers don’t normally pitch down the center line like this. They are usually a few feet to one side or the other depending on their handedness, but, as with the other assumptions, this one is “close enough”.



One thing we can’t ignore is that the bat is not level when it strikes the ball. This is a common simplification, but in our case it is something we need to be more accurate about if we want to get the right answer.

If you think about it, you will realize that the bat is almost never level during a swing—for it to be level the ball would have to be above letter high. That’s not a strike, and few batters will swing at a ball that high unless badly fooled. More typically, the ball is about thigh high. That puts the bat at an angle of roughly 45 degrees. So we have our third assumption:

4) The bat hits the ball at angle close to 45 degrees. Like so:





Figure 1: Here's a typical major league swing mere moments before contact. Notice that the angle of the bat is in the neighborhood of 45 degrees.

Now I’m not going to try to sell you on the idea that collisions in three dimensions are easy to visualize. They most certainly are not, but let’s look at some boundary conditions in a single plane that are easier to come to grips with.

First, we need to backtrack a little from the last assumption we made about the bat being at 45 degrees. We’ll get there a little later, but we need to start with some simpler cases first. Let’s take the case of the bat being parallel to the ground. We have already established that this is not a very good approximation of a real-life swing, but it’s a good starting place since a swing in one plane is easier to visualize. The thing to focus on is where, relative to the center line of the bat, the ball is struck. If we strike the ball dead center, it will start its flight level to the ground, and since our cylindrical bat is perpendicular to the path of the pitched ball, it is heading straight back at the pitcher’s mound. With me so far?

Now let’s imagine the bat hits a little below the center of the ball. In this case, the ball will be hit into the air. The lower the bat gets, the greater the vertical angle of the ball's path upward. The reverse is true, also. If our bat is too high, the ball will be sent toward the ground. This is an intuitive result.

Our second boundary case is when the bat is perpendicular to the ground. Imagine Alfonso Soriano hitting a ball off his shoelaces as only he is able (and willing) to do. Now, the effect of any deviations along the center line of the bat changes the direction of the hit ball instead of changing the trajectory. If we are off a bit to the left, the ball heads off to the right, and vice-versa. If you threw a ball at a round post you’d get a similar effect.

So we have established our two boundary states: Any deviation with a level bat changes the trajectory of the ball, while deviations with a vertical bat change the direction.



Let’s get back to our original model. We assumed a bat angled at 45 degrees, not coincidentally halfway between boundary one (level bat) and boundary two (vertical bat). What this means is that deviations from the center line of the bat have both a trajectory component and a directional component. Thus, a low swing tends to result in a flyball to the opposite field, while a ball hit with the bat being too high will tend to be a groundball to the pull side. Even though we assumed our bat was perpendicular to the flight of the pitched ball (that is, not pulling the ball), we can still account for groundballs to the pull side of the field. It’s all in the physics.

You can test this explanation with a simple experiment. Throw a ball at any cylindrical object, set at 45 degrees—an aerosol can and a ping-pong ball work nicely. Just hold the can at arm's length with one hand and toss the ball with the other. I guarantee that groundballs will go to one side and flyballs will go to the other. If you hit it dead-on, the ball should come straight back.

Now we know why right fielders have to be better fielders than left fielders: Because more batters hit from the right side than the left, right fielders are the ones who have to field many more poorly hit bloopers. Likewise, third basemen have to be on their toes to charge poorly hit grounders that come their way.

Now let’s take a look at why pull hitters are also flyball hitters.

Since pull hitters tend not to hit the ball straight back up the middle, we’re going to eliminate one of our assumptions. We no longer want to keep the bat perpendicular to the path of the pitched ball so we are discarding assumption three. Since we are looking at pulled balls, we want to know what happens when the bat moves further into the swing and is no longer striking perpendicular to the pitched ball.

Once again we will backpedal a bit to set up some boundary conditions—in fact, the same boundary conditions we already used. Once again, looking at the bat parallel to the ground, it is fairly easy to imagine that the further the batter gets into his swing, the more the ball is directed to the pull field. The ball will be deflected further and further toward the pull field the further along the arc of the swing the bat travels. As before, the level bat model is intuitive for most people.

Now let’s look at the boundary where the bat is perpendicular to the ground. As the bat moves further into the swing, the ball is projected at a higher and higher trajectory. Dave Kingman’s famous “pop-up that never came down” that was hit into the roof of the Metrodome was the result of a swing on a ball low and inside. The bat was very close to perpendicular. He was way out in front of the ball and hit it almost straight up. Most pop-ups are mishit, but this ball was tattooed—just not in the right direction. Of course, Mr. Kingman was not known for his disciplined hitting. That was another ball that most players don't offer at.



As before, the most realistic approximation is a 45-degree swing angle, and, as before, it combines the effects of both the boundary conditions. As a player turns on a ball, there is a directional component and a trajectory component to the result. The further into the swing the batter gets, the more a ball is pulled and the more it is lifted into the air.

If you pay close attention when watching a baseball game, you will see players hit over the ball, but the result will be a line drive instead of a grounder because they pulled it. What would have been a grounder when the bat was perpendicular to the flight of the baseball becomes a line drive when the ball is pulled. Likewise, hard line drives that are hit with the bat perpendicular to the path of the pitched baseball often become home runs when pulled.

If you grab your trusty aerosol can you can prove this through experimentation, although it’s a little trickier than the first test. You will need to hold the can at a 45 degree angle in two planes. Hold it at an angle the same way you did in the first experiment and then tilt the end the batter would be holding away from you. You will see now that almost all the ping-pong balls that strike the can will be flies and go to the pull side.

You may be thinking, “He just told me that players hit flies to the pull side when only a few paragraphs earlier he said they go to the opposite field.” Somewhat true, but here’s the distinction: Poorly hit flies go toward the opposite field while well hit flies go toward the pull field. This is another reason right fielders are much busier than left fielders. A large number of flies that left fielders see are traveling over their heads and into the bleachers. They see fewer balls and many of those that do head their way aren’t playable.

Click here to learn about THT's download subscriptions.]]> Matt Lentzner 2007-07-13T04:03:15+00:00