Crossing the Bridge: A closer look at what happened to Barry Zito

(Previous articles in this series Zito1, Zito2, Zito3)

This series of articles started with “A Bridge Too Far…..” We are now at the “Zito Bridge,” but before we attempt to cross, a brief review of how we got here.

1. There is no such thing as good pitching mechanics, simply because no one can agree as to what they constitute. What does exist are good throwing mechanics as defined by physics, biomechanics, kinesiology, physiology and motor learning and control. Throwing a 95 mph fastball, no matter who throws it, requires the same physics.

2. Pitching is doing everything necessary to defeat the batter. An important (most important?) aspect of pitching skill is throwing the baseball. It becomes a lot easier to get the batter out if you possess speed, location and movement. Speed, location and movement are a result of effective development and use of the kinetic chain.

3. Throwing a baseball is the result of optimizing the kinetic chain/sequence processes. There is the physical component to throwing; i.e., muscle, connective tissue, nervous system or what might be called the “active” part of throwing a baseball. There is also a mechanical (passive) component, governed by the principle of the compound pendulum, the sequential transfer of momentum from feet to fingertips.

4. The mechanical (the mechanics in “pitching mechanics”) aspect of throwing is exclusively the product of rotation and maintaining connection to that rotation.

5. The body throwing a baseball is a “throwing system” and is subject to the principles of complex dynamic systems. Complex dynamic systems exhibit chaotic behavior; simply stated, small changes in any aspect of the throwing process can have significant (positive or negative) effects on the final result.

6. Left handers, by virtue of throwing with that arm, can succeed in spite of throwing the ball with less than maximum efficiency. Many left handers never learn how to throw the ball with the greatest efficiency and effectiveness.

7. Throwing instruction is nonexistent at the professional level, and what constitutes good throwing mechanics is not understood at a level necessary to help players such as Barry Zito. Players are drafted because they know how to throw the baseball (velocity, velocity and more velocity). A player’s throwing skill is developed through a trial and error process, starting when the player is very young. All that professional baseball can hope to do is turn throwers into pitchers.

These are some of the factors that not only explain what happened to Zito’s fastball, but are the keys to finding it again.

In the first article I observed similarities between what happened to Steve Avery and what is potentially happening to Zito. Both are/were 6-foot-4, 200-pound left handers who burst on the MLB scene at a young age and experienced great success for several years, followed by a downward spiral. Zito’s apparent decline is occurring over a longer period, but there are significant similarities.

Zito and Avery both have/had marginal throwing mechanics, a common characteristic of left-handers. They also possess physical abilities and attributes (size, strength), and of course, most important, both throw left handed.

The reason generally given for Avery’s decline is an injury he suffered in September of 1993. The injury was reported as a torn muscle under his armpit.

He was selected to the All-Star team and had a record of 16-4 entering the Sept. 12, 1993 game against the San Diego Padres. Avery lost and sustained that injury. Many blame Avery’s heavy workload as a young pitcher for his injury; he had started 135 major league games before reaching 24. Avery was never again the same pitcher, although he ended the year 18-6 with a 2.94 ERA, a phenomenal record for a team’s fourth starter. (Wikipedia 2008)

In 1994 Avery had a record of 8-3, and other than his ERA, his statistics were in many ways better than previous years particularly his strikeouts to innings pitched ratio. Physical examinations showed no indication of problems from the previous armpit injury. What is not generally known is the problem Avery was having on the home front.

Avery began to struggle in 1994, a season in which he spent much of the season traveling between Atlanta and his home in Detroit after his wife gave birth prematurely to a son weighing just two pounds. Avery began the season 5-1 but saw his ERA balloon as he dealt with his personal trauma. “It was hard to do something when your heart was elsewhere,” Avery told Baseball Weekly after the season. “Looking back on it now, I can say it affected me more than I thought.” ( )

A Hardball Times Update
Goodbye for now.

What actually happened to Avery? As I said previously, when I first saw Avery throwing a baseball for the Red Sox in 1997 I was very much “intrigued” (shocked) by his throwing mechanics. His mechanics were quite different from what, at the time, I considered good throwing mechanics. I became very curious as to how his 1997 throwing mechanics compared to his 1991-1993 mechanics. I was able locate video clips of him from those years and did an extensive comparison of the 1997 Avery to the 1991-1993 Avery.

To my surprise, Avery’s 1997 mechanics, as strange as I thought they appeared, were not that much different than his 1991 mechanics. (Welcome to the wonderful world of the human body throwing a baseball—there is an infinite number of ways to use your body to throw the ball.) I learned a lot about how the body throws a baseball from Avery’s clips, but possibly the most important lesson that his mechanics taught me is that small changes can have significant effects on the final result. Years later, I came to understand this phenomenon as chaotic behavior, a property of dynamic systems.

My speculation is that possibly the injury did play a role in Avery’s demise. It altered how he threw the baseball “just enough” (as opposed to a chronic debilitation) to compromise his ability to throw with the same effectiveness he had before the injury. And, quite possibly, the injury combined with the problems he was having with his family (and subsequent loss of playing time) created a situation where his body forgot how to throw the baseball.

One of the most powerful mechanisms for destroying a player’s ability to throw effectively is the need to perform if there is some debilitating factor present (Dizzy Dean’s broken toe being one of the more famous examples).

Several years ago I did an analysis of Avery’s mechanics for a friend who is the pitching instruction coordinator for a major league team. This analysis is available at .

Avery at his best was more of a north-south thrower, which is the precursor to the throwing problems Avery developed (Avery began pushing the ball).

Before 1997,Avery possessed an east-west component to go along with his north-south delivery. For whatever reason,s Avery lost most of his east-west component, resulting a significant decrease in the mechanical “step up” effect (whip effect, compound pendulum). I also call this disconnection, of his arm from the rotation of the torso.


Figure 1. 1997 Steve Avery on the left. 1991 World Series Avery on the right.

The bottom line is that Avery not only lost 4-5 mph off his fastball but also suffered movement and location problems. Why? Because he became much more dependent on muscling the ball as opposed to optimally throwing the ball.

I see the same thing happening in Zito’s delivery.


Figure 2 on the left Zito 2008 throwing 84 mph. On the right Zito 2000 throwing 89 mph.

Seeing these problems is so difficult because at the major league level competition it takes only a small change in mechanics to decrease velocity by 5 mph (or more), making it virtually impossible for the coach or instructor to see the difference. And seeing is only at best half the problem. Seeing is one thing. Fixing is another.

The two tools I have found most beneficial for understanding how the body throws the baseball are physics and physiology—the combination is also call biomechanics. Pitching mechanics or throwing mechanics are both poor cousins to what is really happening when the body throws the baseball.

In my previous article I tried to show how physics simulations are used to better understand the throwing process. From a physiological (and kinesthetic) perspective I find three-dimensional simulations of the throwing process vitally important to understanding how the body throws the baseball. To create these simulations you have to understand not only the physics of the throwing process but also how each body part is contributing when it throws the baseball.


Figure 3. Zito 2008 3D throwing simulation.

Pushing the ball is the most common and also the most insidious throwing problem. A common form of pushing is also described as muscling the ball. Pushing the ball occurs when there is a break in the rotational sequence (kinetic chain). Attempting to get extension toward home plate is the most common cause of disconnection. Attempting to get a release point out in front or on top of the ball truncates rotation and contributes to a linear finish (disconnection). As previously stated, a north-south delivery has a greater propensity for disconnection.

You can be a north-south pitcher if you have a certain amount of east-west (translational) rotation. But even the smallest loss of translational rotation can spell disaster for a north-south pitcher, as is the case with Zito.

Disconnection occurs when rotational connection is lost between successive elements of the kinetic sequence. The simulation in Figure 4 demonstrates the disconnection principle.

On the left-hand side we have a “connected” compound pendulum. On the right-hand side we have a compound pendulum which is connected until shortly before what would correspond to releasing of the ball (or making contact with the bat).


Figure 4. Compound pendulum on left staying connected. Compound pendulum on right disconnecting just before “release” of the ball.

The compound pendulum (on the left) stays connected achieves a maximum velocity at release point of the ball of 70 fps (feet per second). The compound pendulum on the left (that is disconnecting just before release) achieves a velocity just prior to release of 50 fps.

There are a number of rotational centers when throwing the baseball. But the most important ones based on my observations are rotation around the front hip joint, rotation of the shoulders around the upper spine, and rotation of the scapular as it slides along the rib cage. These of the primary rotational centers responsible for creating a whipping action.

Also critical to the whipping action is creating the “loop” in the throwing arm. This loop is composed of raised-forearm-upper arm-humeral joint. The loop is created primarily by the inertia of the forearm during rotation of the shoulders and bending forward to the upper torso. The key here is rotational connection must be maintained—a constant pulling action of each successive segment of the chain toward a rotational center point.

For emphasis I have illustrated the rotational path of the connected pendulum and the rotational/disconnection path of the disconnecting pendulum.


Figure 5. Path showing connection versus disconnection

In comparing clips of Zito from early 2000 when he was throwing 89-90 mph to now, there are small but significant differences in his delivery.


Figure 6 on the left Zito 2008 throwing 84 mph. On the right Zito 2000 throwing 89 mph.

The first thing that I noticed was the height of the glove side arm during the throwing process. If you look at Zito’s delivery in 2000, he separates the glove and ball hands in a more horizontal manner—more in the transverse, or east-west plane). In 2008 he has much more of a teeter-totter release. The glove hand is raised much higher during the throwing process.


You also can see that his front shoulder is elevated much more in 2008 as compared to 2000.


Also, look at the height of the front foot at the same point of delivery. Not only are his shoulders elevated, but his front hip is also elevated. Again, this promotes “teeter-totter” and is cannibalizing rotation around the spine.


If we look at the body just after release of the ball you can see that he’s bent over more. Look at the position of his head—it is bending down almost below the shoulder line.


One potential consequence of losing east-west rotation is a decrease in forearm layback (action rotation of the shoulder). That rotation is critical in terms of developing a whipping action. There are several critical aspects in creating this loop. The greater the amount of forearm flexion, the greater the potential throwing velocity. In the picture below you can see that the amount of forearm flexion in 2008 appears to be somewhat less than in 2000.


What’s also critical about the whipping process is getting the forearm to lay back in the rotational plane of the shoulders. The greater the north-south (teeter-totter) delivery, the greater the potential for the forearm to not lay back in the rotational plane of the shoulders.

And then we have that “funky” action of the posting legs after release in 2008, as compared to what I call a well-behaved posting leg in 2000.


More often than not, I learn as much about a player’s throwing effectiveness from watching what happens to the pitcher’s body after release as what happens before the release. In particular, look at how Zito’s rear leg passes through what I consider a very awkward-looking configuration as compared what his posting leg is doing in 2000. This indicates pushing the ball forward.

The action of that posting leg also suggests loss of rotation of the pelvis and upper torso around the front hip joint.


The back leg action in 2008 as compared to 2000 possibly indicates that Zito is not rotating around the front hip joint as efficiently as he did in 2000.

It is possible that Zito, like most pitchers, coaches and instructors, believes that the further he releases the ball out in front , the greater his advantage. Nothing could be further from the truth.

Attempting to release the ball out iront or extend to the batter is the quickest way to degrade velocity and movement. It becomes a vicious cycle, because as he tries to release further out in front and get more on the ball, he becomes more linear, which promotes more muscling of the ball and loss of mechanical advantage. The more he tries to muscle the ball, the less control he has. One of the most telling effects of this is missing high with the fastball

Tthese differences in Zito’s 2008 mechanics as compared to his 2000 mechanics are enough to create a 4-5 mph velocity decrease along with control problems.

In closing I’ve taken the liberty to construct a 92 mph Barry Zito.


Figure 6 A 92 mph Barry Zito.

Should a representative of the Giants (or Zito) wish to contact me I would be very happy to share my thoughts on what it takes to design and implement a 92 mph Zito…… image

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