Brandon McCarthy. RHP, 6' 7", 200 lbs, Born: July 7, 1983. Okay, he's not a prospect, but I'm not renaming my series because of one guy.

Since coming to the Texas Rangers, McCarthy has struggled with two things: health and command. It's a little early to declare either of those as "overcome," but so far this season he looks healthy and strong.

McCarthy's fastball has generally been an 89-92 mph offering which, by itself, is nothing special. Two other elements make it a pretty special pitch, though. His high release point gives his pitches a great downward plane to the strike zone, and he gets excellent "rising" action from a crazy amount of backspin. The combination of these two gives his fastball a unique look for the batter.

For someone with a soft landing on a flexed front leg, McCarthy gets very little power from his legs. In this case, when his front foot lands, his legs stop contributing to forward movement and the following hip rotation is purely inertial. His trailing hip even drags his back foot like an anchor.

McCarthy has a tendency to drag his arm behind his body when he throws his fastball. Arm drag occurs when the pitcher's body gets too far ahead of the arm. In other words, the arm lags behind the body. This is mostly a timing issue, but it can lead to health problems in the shoulder. Performance-wise, arm drag tends to lead to poor command and a preponderance of pitches that are high, outside, or both.

In this video, his front shoulder opens a little early, but he keeps his pitching arm from lagging behind.

When McCarthy pulls his front shoulder, he's using a large number of his trunk muscles. To drive his pitching shoulder forward, he uses the rest of his trunk muscles. By breaking his shoulder rotation into two separate actions, McCarthy's trunk muscles do not work in concert. The result for McCarthy is slower, less powerful shoulder rotation with a large degree of forward flexion in his trunk.

For an example of someone who uses his trunk insanely well, Neftali Feliz has both a powerful shoulder rotation and a large degree of forward flexion (see Texas Rangers Prospects: Neftali Feliz and Tae Kyung Ahn for more details). Notice that Feliz's shoulders rotate together as a single unit, not separately. Also notice that he stays fairly tall, while McCarthy sort of bends in half at the waist.

Rangers blogger Mike Hindman suggested that McCarthy has an inverted W. McCarthy's arms, though, are well past the inverted W shape when his front shoulder starts to open up. He still has a late forearm turnover and a reverse forearm bounce.

It's hard to tell from this angle, but McCarthy's reverse forearm bounce might be exaggerated by some elbow flexion. By this, I mean that he picks his elbow up high enough that gravity plus natural elbow flexion - rather than inertia - appear to be causing some of the ball's downward motion. This view is inconclusive, but I don't believe his ulnar collateral ligament would hold up for very long if inertia alone caused a bounce that large.

As McCarthy drives into his release, he lifts his elbow just above the line across the top of his shoulders. At release, his humerus usually approaches vertical. This prevents forearm flyout - even though he takes the baseball toward first base during his pick-up - and allows McCarthy to powerfully contract his triceps brachii.

McCarthy pronates into his release on each of his pitches, and if you look closely, you can see his elbow pop-up early in the follow-through. This is fairly similar to the pop-up in Dr. Marshall's arm action that he has demonstrated to be a result of using the latissimus dorsi to both extend and internally rotate the upper arm (see Dr. Mike Marshall on MLB Network).

His follow-through is not spectacular but is fairly standard for traditional pitching mechanics. One negative aspect is that he falls so dramatically toward first base after every pitch. (When he pulls his front shoulder, he's also moving his center of mass in the same direction which causes a balance shift.)

In summary, I think McCarthy could get much better results from his legs and core, but I like his arm action. If he can have success with these mechanics and stay healthy, though, there's no reason to change them.

Ezequiel Rijo. RHP, 6' 4", 190 lbs, Born: September 12, 1990. Rijo pitched in the Dominican Summer League in 2008 and posted some interesting numbers including 48 hits (only 2 homeruns) and 41 strikeouts in 71.0 IP. I don't recall anything about his stuff, though his numbers suggest a fastball with decent movement but not overpowering velocity. In the video, you can see three pitches being thrown: a fastball, a change up, and a slider that you have to look closely to see.

I went pretty long on McCarthy, so I'll keep Rijo's report nice and short. Let's take a look at the video.

Rijo's leg drive is shockingly similar to McCarthy's, but Rijo's looks more intense and appears to lead to better hip rotation.

Interestingly, Rijo also pulls his front shoulder before driving his pitching shoulder. Rijo's glove arm is only slightly more aggressive than McCarthy's glove arm, and his result is the same as McCarthy's - poor shoulder rotation with extreme forward flexion of the trunk.

Rijo has a very sound ball pick-up. We can't see his whole pick-up, but we do know that he doesn't take the ball behind his back and that his elbow doesn't reach shoulder height before the ball. Unfortunately, he still has a late forearm turnover and a large reverse forearm bounce.

Forearm flyout is another potential issue for Rijo since his arm isn't really close to vertical except for his change up. His pick-up helps limit his forearm flyout risk. Because he never takes the ball laterally toward first base, his lateral acceleration of the ball toward third base is very minor.

His follow-through is fairly average, and he gets himself almost immediately into an excellent fielding position.

This video is possibly the best example I've found of what Dr. Mike Marshall's arm action is supposed to look like. The catch is that the pitchers in the video aren't throwing baseballs. The pitchers are performing exercises from Dr. Marshall's wrist weights program.

4 of Dr. Marshall's students are shown here doing different things that include his wrong foot slingshot, wrong foot loaded slingshot, and pendulum swing wind-up drills.

One thing I've noticed repeatedly is that despite the straight-line acceleration of the heavy weights during these exercises, Dr. Marshall's students routinely demonstrate a dramatically different arm action when they throw baseballs.

The main difference is where the arm drives the baseball. In the weighted exercises (iron balls and wrist weights), his pitchers unquestionably apply force in a nearly straight line that results in extension that is simultaneously away from the pitcher's body and toward the target. When throwing a baseball, however, his pitchers apply a lot of upward force that results in extension that is away from the pitcher's body but toward the sky instead of the target.

[Added at 12:30 PM, Monday, April 27, 2009]

One of Dr. Marshall's pitchers from the video has emailed me and asked that I clarify the difference that  I see. In short, Dr. Marshall writes that the driveline height of the baseball should be just above the ear. This description perfectly fits with the driveline height for the weighted exercises. In the high-speed video I've seen of Dr. Marshall's pitchers, the driveline height for their baseball pitches results in a release point that is almost a full arm's length above the ear.

[/Added]

Some exercise specialists believe that the extremely heavy weights train the muscles to fight gravity. As the pitchers step up the weight increments, their muscles learn more and more to oppose gravity. Holding up a 20-pound wrist weight requires more than 60 times the force that is required to hold up a 5-ounce baseball, so when one of Dr. Marshall's pitchers performs his arm action with a baseball, his body and arm are accustomed to applying much greater upward force than is necessary.

This is one explanation for the upward extension. It makes perfect sense even to a layman, but I don't believe it accounts for all of the differences.

Dr. Marshall himself focuses on the principle of specificity of training - that a pitcher should learn/train to pitch baseballs by pitching baseballs - so his interval-training programs make baseball pitching a part of the daily routine.

So why then do his pitchers have a distinctly different arm action when throwing baseballs compared to when they "throw" heavy weights? Truthfully, I don't have that answer. It could be related to old muscle memory, or I may have misinterpreted Dr. Marshall's ideal arm action.

If you know the answer, I'd love to read it.

Michael Main. RHP, 6' 2", 170 lbs. The Texas Rangers selected Michael Main 24th overall in the 2007 MLB First-Year Player Draft. An extremely athletic two-way player in high schol, Main was on several draft boards as an outfielder.

I became a Main fan well in advance of the draft and thought the Rangers missed their chance at him when they selected Blake Beavan with the 17th overall pick. I was thrilled that he was still on the board at #24, and I was ecstatic when they called his name.

Main has been impressive since being drafted, but at instructs this past fall, Rick Adair, in an interview with Mike Hindman, had the following to say:

He's throwing an extremely high percentage of major league-quality pitches right now. Michael just has the ability to take in coaching, information and come up with ideas. His makeup is tremendous. Mentally he's easily the most polished guy out of high school I've ever been around.

Coming into this season, Rangers fans were more excited than ever to have Main in the farm system.

Main might have the latest forearm turnover in the history of baseball. When his front foot finally plants, his elbow still hasn't reached driveline height, and he's in a borderline inverted L position. This is usually a flag for more serious elbow torque, but he appears to almost completely avoid the reverse forearm bounce pitfall.

Like Tae Kyung Ahn, Main lands with a lot of weight on his front leg, but what Main does differently is very important. Main keeps his hips and shoulders closed very well unlike Ahn, and he manages to keep his center of mass moving forward where Ahn's momentum was more dramatically slowed at landing.

You can see that Main pulls off the rubber fairly hard without dragging his foot. It's likely that he's pulling himself forward with his front leg and therefore creating more ground-reactive force for his pitch. A lot of pitchers push back to help their hip rotation, but Main's "pull" doesn't seem to negatively affect his hips. The lack of a foot drag definitely helps his back hip come forward freely.

Main's arm doesn't appear to be doing a whole lot of work. That's usually a good thing, but Main's arm does all of its work in a shorter period of time than just about every other pitcher on the planet because of his extremely late hand-break and ball pick-up. This leaves less room for error and can lead to timing issues that adversely affect command and velocity when the timing is just slightly off.

Main pronates into his release very well.

His initial arm deceleration is good, and he drives his shoulder all the way through release to help ease rotator cuff stress. His final follow-through is fairly average with a little bit of arm wrap but no major red flags.

Kyle Ocampo. RHP, 6' 3", 195 lbs. Another right-handed pitcher, Ocampo was also a member of the 2007 draft class. Taken in the 13th round, Ocampo was a raw pitching talent with some herky-jerky mechanics. He signed too late to play in 2007, and made his debut in the Arizona Rookie League as a 19-year-old in 2008: 52.0 IP, 47 H, 19 BB, 56 K, 3.29 ERA, 1.27 WHIP.

At instructs after the 2008 season, Jason Cole of LoneStarDugout.com posted an interview with Kyle Ocampo (subscription required). In the interview, Ocampo breaks down his pitching arsenal - 4-seam fastball, 2-seam fastball, curveball, slider, and change up - and discusses the adjustments he's making to become a better pitcher.

Ocampo has a very noticeable head jerk, but overall, his mechanics are much smoother and cleaner than when I previously saw him at spring training in 2008. He still has a lot of wasted back-and-forth movement. For example, he kicks his leg out, picks it up, and then tucks it back where it would have been if he'd just picked it straight up. Like most pitching coaches, I tend not to like wasted movement because it represents an unnecessary expense of energy.

As long as his command remains decent, the Rangers aren't likely to mess with his delivery too much.

Ocampo's leg drive is very energetic, but once he lands, his legs are done. His back leg sits there as dead weight while his front leg does nothing more than create a trunk pivot at his front hip.

He picks the ball up late and has a pretty late forearm turnover, but he, too, appears to avoid a significant reverse forearm bounce. Ocampo does this by picking his elbow up pretty steadily to his release point; this also helps limit forearm flyout and gives him a near-vertical forearm at release. (A vertical forearm allows a pitcher to throw a greater variety of pitches. From there, a pitcher can safely create back-spin, front-spin, side-spin in either direction, and anything in between.)

Ocampo doesn't appear to pronate into his release on either his fastball or his change up, though he clearly pronates after release.

His follow-through is fairly clean, but his forearm appears to slam into his front hip. This shows a lack of body control, but since his forearm takes the beating, it shouldn't lead to shoulder issues.

Ocampo is still a work in progress, so I expect continued refinement of his mechanics over time. He's got the stuff, and it's just a matter of keeping him healthy and of finding consistency and command of enough quality pitches to keep moving through the system.

Note: The last pitch in Ocampo's video is a change up. His mechanics look a little different to me when he throws it. I doubt that it's as obvious at full speed as it is in slow-motion.

In limited action in 2008, Nelson Cruz finally started hitting Major League pitching to the tune of .330/.421/.609. Given the small sample size, people openly questioned whether he had actually turned the corner.

Through Friday, April 17, 2009, Cruz was off to a .282/.356/.718 start, more or less a continuation of his 2008 success. Using PITCHf/x data through the first 10 games of 2009 and some stats from Nelson Cruz's FanGraphs profile, here's a little plate discipline analysis to see if it supports his impressive start.

The black boxes in these charts are approximations of the actual strike zone. Based on average PITCHf/x data for Cruz's at-bats, the bottom of Cruz's strike zone is about 1.6 feet from the ground, and the top of his strike zone is about 3.4 feet from the ground. The left and right edges of the zone are approximated at 1 foot to either side of the plate based on half the plate's width (8.5 inches) plus some wiggle room for pitches that scrape the black (3.5 inches). (NOTE: All location graphs are from the catcher's perspective.)

The first chart shows us what Cruz has been swinging at by location and by pitch type.

Based on this chart, Cruz has mostly been swinging at strikes. According to his O-Swing% at FanGraphs, only 20.2% of these pitches are outside of the strike zone. That is the lowest of his career. Since his 2006 Rangers debut, his O-Swing% has dropped every season - 29.4% in 2006, 26.5% in 2007, and 23.1% in 2008.

Notice that Cruz hasn't swung at many pitches near the bottom or near the outside edge of the zone. This has helped Cruz lay off of breaking pitches away. Through 10 games, Cruz had not swung at a single pitch off the outside edge of the plate.

The second chart shows us what Cruz hasn't been swinging at by location and by pitch type.

This chart fills in the obvious holes from his swings chart. There are a lot of pitches in the zone low and away that Cruz has not swung at. According to his Z-Swing%, Cruz has swung at 78.5% of pitches in the zone. Based on that stat, the chart doesn't exactly match up. It appears that he's been taking pitches in the zone more often than 21.5% of the time. This could be the result of the PITCHf/x strike zone not matching up with the zone being called by the umpires.

Without getting in too terribly deep, here's a quick look at the righty-lefty split broken down by location and pitch result. The small sample against lefties in the first 10 games doesn't give us much to look at, but the righties scatter plot is interesting.

The PITCHf/x strike zones for Cruz appears to be pretty accurate. Keep in mind that some of the strikes outside of the zone were swung at.

Let's look at Cruz's Z-Swing% again. My rough count based on my unofficial strike zone suggests a 61:23 ratio or a 72.6% Z-Swing%, which would still be a career high for him. From 2006 through 2008, Cruz's Z-Swing was very steadily between 70% and 71%.

This year, he's swinging at strikes more often, but he's also swinging at fewer pitches overall - 46.8% in 2009 versus 50.8% in 2006, 49.6% in 2007, and 47.1% in 2008.

April 19, 2009 Update: Cruz has reached base safely in all 12 games this season on 13 hits and 7 walks against only 10 strike outs. He is now hitting .289/.377/.667.

The numbers and charts say he's being more selective than ever. This can only be good news for Cruz, the Texas Rangers, and their fans. I believe that Nelson Cruz has finally arrived.

Some other observations:

• Very few pitches have been thrown low and in to Cruz. I wonder if his AAA scouting report says to stay away from that quadrant.

• Righties stand a good chance of getting Cruz to put the ball in play by throwing him up and in.

• Cruz's first-pitch strike percentages by year: 62.3% in 2006, 63.4% in 2007, 52.6% in 2008, 51.0% in 2009. It's a small sample size and might not mean anything anyway, but it is interesting.

• One step further, Cruz is seeing fewer strikes than ever: 52.5% in 2006, 52.4% in 2007, 50.2% in 2008, and 45.7% in 2009. Combined with the stat above, I'm pretty sure this means something.

• One concern: what happens when opposing pitchers start hammering that outside corner?

This aired back on March 25, 2009. The link below will take you to a 7-minute segment from MLB Tonight which airs on MLB Network. In this clip, Harold Reynolds is joined by Dr. Mike Marshall and his left-handed student Joe Williams.

With only 7 minutes in which to work, Dr. Marshall has to skim over a lot of things, but he sums up his arm action very succinctly. He briefly explains the muscles that are involved in his arm action and mentions how pronation helps protect the elbow.

Dr. Marshall also has Joe demonstrate a couple of drills. Pay special attention to the second base pick-off drill. It's a drill he has mentioned in the past when talking about re-training traditional pitchers to correct the flaw of horizontal shoulder flexion.

With the football drill, Dr. Marshall and Joe show Harold how to throw a pronated curveball. The video isn't the best, but if you look closely and use some imagination, you can see the ball spinning forward instead of backward.

MLB Network: Dr. Marshall talks pitching
[Update 2019: Link no longer works after MLB.com made changes to their video library.]

Post questions and comments here, and I will do my best to address them.