Scouting Craig Fritsch, Baylor University

Trip Somers • March 13, 2009 • Scouting

Another draft-eligible sophomore out of Baylor University, Craig Fritsch (Round Rock HS, TX) is listed at 6' 4", 180 lbs. According to Baseball America, Fritsch is the #6 draft-eligible sophomore prospect for the 2009 MLB First-Year Player Draft and the #38 overall college prospect.

This past summer, Fritsch was among the top prospects in the Cap Cod League, checking in at #18 on the Baseball America list (subscription required). The brief report on Fritsch, mentions a low 90s fastball, "a good slider and a usable change up."

Fritsch pitched against Rice University on Sunday, March 1, 2009 at Minute Maid Park during the Houston College Classic.

Game: March 1, 2009 vs. Rice University

Pitcher IP H R ER BB K
Fritsch, Craig 5.0 7 6 4 2 7

Fastball. True to the report from the Cape, Fritsch's fastball sat at 90-92 and hit as high as 94. His stride and low 3/4 release give him a wide angle to the plate, so all of his pitches have "hidden" movement to his glove side. Fritsch gets good sink and arm-side run on his fastball that counters this "hidden" movement and augments the pitch's life. He had good control, but was a little bit wild in the zone as evidenced by the 7 hits he allowed.

Slider. His slider really looks like a side-arm or sweeping curveball to me. Fritsch's low arm angle reinforces my belief that this pitch is really a curveball. That said, the pitch has strong arm-side-to-glove-side movement as well as some downward plane. This is a great college breaking pitch, and it should play very well against wood bats. It should become at least a Major League average offering.

Change up. Fritsch's change up is quite an interesting pitch. He gets good sink on the pitch, but it doesn't fade to the arm side. This pitch actually cuts to the glove side, almost like a slow slider. Fritsch's wide-angle release point could be the sole cause. In this game, he kept it down but mostly out of the zone. To me, it looks like it can be Major League average, though it needs some work.

Mechanics. Have a look at the video.

His stride is a decent combination of tall-and-fall and drop-and-drive. Fritsch stays tall early, and then bends his leg to get a strong forward push. He starts to pull off the rubber, but drags his toe, preventing his hips from continuing forward through the pitch and stopping his shoulders from fully rotating until after primary deceleration.

You can also see that Fritsch starts his stride in the middle of the rubber and lands outside the third-base edge of the rubber. He lands very closed, but this is part of why his pitches have such a unique angle to the plate. Landing closed can lead a pitcher to throw across his body, but Fritsch gets enough of a hip turn to avoid it.

Fritsch starts to pick the ball up with something like a pendulum swing, but he cuts it off very early to hyperabduct his humerus. He has a pretty strong scapular load, but he gets his forearm vertical before foot plant.

He has a pretty late forearm turnover. You can see that it doesn't fully lay back until just before release. While his forearm is laying back, Fritsch moves his elbow up. This limits the amount of reverse forearm bounce that takes place by reducing the rotational inertia of the lay back. In the side views, the ball doesn't appear to change height at all, but in the front views, you can see the ball dip a little right before Fritsch releases it.

Fritsch shows good pronation on his pitches, but his follow-through is a little rough. The strong lateral components introduced by his stride and his scapular load cause his arm to fly across his chest after release. This can put a lot of stress on the infraspinatus and teres minor muscles of the rotator cuff, particularly when a pitcher's shoulders stop rotating before the follow-through like Fritsch. This is a small concern going forward, but may never become an issue.

Overall. Fritsch's fastball is probably already Major League average, and his slider isn't far behind. He needs to work on command of his change up, and it could become fringe-average. His control is a plus, but he lacks true command of his arsenal.

He throws a lot of strikes, probably too many, and doesn't fool college hitters as often as someone with his stuff should.

Fristch has some pretty good college stuff, and he has some projection left in his slim frame. In time, he stands a decent chance of having three pitches that are at least Major League average. He's not there yet, but if his command comes around over the next couple of months, he could see his draft stock shoot up significantly.

Scouting Gerrit Cole, UCLA

Trip Somers • March 6, 2009 • Scouting

In the 2008 MLB First-Year Player Draft, Gerrit Cole was drafted 28th overall by the New York Yankees but ultimately chose to go the college route at UCLA.

According the the Major League Scouting Bureau's pre-draft report, Cole has the ability to throw three pitches for strikes: a mid-to-upper 90s fastball, a firm change up, and a slider with future plus potential. The report also warned about Cole's poise and his tendency to throw across his body.

The 6' 4", 215 lb Cole pitched against Baylor University at the Houston College Classic on February 28, 2009. Here's what I saw.

Game: February 28, 2009 vs. Baylor University

Pitcher IP H R ER BB K
Cole, Gerrit 6.0 2 1 0 5 8

Fastball. Cole's most effective pitch was 95-97 mph through the first couple of innings and hit 99 more than once. The pitch had strong arm-side run, but the "plus sink" mentioned in the Scouting Bureau report was non-existent, replaced by more of a rising action. As evidenced by the 5 walks, Cole's command was not as sharp as advertised, but with 8 strikeouts and only 2 hits allowed, he was effectively wild.

Slider. Cole was throwing a very hard slider in the mid to upper 80s. The potential of this pitch is obvious, though he has a long way to go before it can be called a plus pitch. Too often, the pitch was flat with a lazy break, but the pitch did reveal its promise on occasion with a sharp, late break when he kept it in the 84-85 mph range. He needs to improve both his command of the pitch and its consistency.

Change up. The Scouting Bureau reported this pitch as "too firm at 79-80 mph," which is a funny statement since that represents a 15 mph separation from his fastball. I was actually shocked by his feel for this pitch and by the confidence with which he threw it. In this game, it had good fade and sink, and he clearly commanded it better than his other two pitches. His slider has better potential, but this day, his change up was the better pitch.

Mechanics. According to the Scouting Bureau, Cole has "some mechanical issues" and frequently throws across his body. Let's have a look.

Starting at his legs, you can see a little bit of why he throws so hard. After gathering himself, Cole has a powerful forward stride. He drives through his landing and then pulls his back hip and leg forward, allowing him to continue rotating his hips. This is great action from his back leg.

He lands on a slightly flexed front leg, from which he gets a strong push back to help rotate his hips. This is good for generating a high rate of hip rotation, but it halts the forward movement of his center of mass.

He stands far to the glove side of the rubber and strides slightly toward the third base line, landing slightly closed. Landing closed tends to cut off hip rotation and shoulder rotation, generally forcing the pitcher to throw across his body to get the ball to the plate. In Cole's delivery, it doesn't really cut off his hips or shoulders, but he still throws across his body.

Cole breaks his hands near his belly button but has a pretty healthy pick up. It isn't quite a pendulum swing, but his elbow and hand reach shoulder height at approximately the same time. After his front foot lands, he really begins to accelerate the baseball.

Thanks to his pick up, Cole does not have an active external rotation component to his late forearm turnover. This allows his forearm to turn over with less violence and results in a rather mild-looking reverse forearm bounce.

Cole's shoulders have only a small reverse rotation, but when coupled with his slightly off-line stride, it results in a long arc-shaped path for his elbow. Acceleration through this arc causes forearm flyout which precludes a kinetic contribution from the triceps brachii muscle.

He pronates after release as most pitchers do, but only on his change up does he actively pronate through his release. He turns his change up over very well as a result.

After primary deceleration, Cole's arm coils back up by his side. This indicates that his arm is powerfully braking itself during deceleration. More than anything, this is a reaction to the violence with which he throws across his body. In the video, you can see Cole's arm finish across his body and immediately bounce back up. The violence in the follow-through could lead to injuries to the infraspinatus and/or supraspinatus muscles of the rotator cuff.

Overall. Prior to the 2008 draft, Cole's makeup and poise were my biggest concerns with him as a prospect. After breezing through the first batter of the game, Cole had some command issues. A walk, a double, an error, a walk, and a wild pitch followed in close succession, but Cole held it together much better than his high school scouting reports suggested. He got through the inning, and threw 5 more very solid innings.

There are still some mechanical issues for him to work on, namely the way he throws across his body and his violent follow-through, but even if he were draft eligible this season, these issues wouldn't likely affect his draft position.

Gerrit Cole has an elite fastball, a solid change up, and a slider with plus potential. His command was off in this outing, but it is typically very good. He's already on the short list of potential #1 overall picks for the 2011 MLB First-Year Player Draft. Over the next two years, he'll stay on everyone's watch list.

Scouting Shawn Tolleson, Baylor University

Trip Somers • March 4, 2009 • Scouting

In his second year back from Tommy John surgery, Shawn Tolleson is expected to be among the top draft-eligible sophomores taken in the 2009 MLB First-Year Player Draft. Baseball America even pegged him as the #29 overall draft-eligible college prospect.

After hitting a groove out of the bullpen last season, Tolleson has returned to the starting rotation for 2009. Through 2 starts, though, Tolleson has yet to find his rhythm. I was on-hand at the Houston College Classic when Tolleson and Baylor squared off against the University of Houston.

Game: February 27, 2009 vs. University of Houston

Pitcher IP H R ER BB K
Tolleson, Shawn 6.2 6 2 2 3 5

Fastball. Tolleson's fastball started out in the upper 80s and might have scraped 90 on a few radar guns but dipped into the mid 80s before he was pulled. The pitch didn't appear to have much sink, but his 10 ground outs and 2 fly outs suggest it was there. His command of the pitch was no better than college-average.

Slider. His slider was all over the place but had good movement when he was able to keep it down. Its break was unpredictable as well, sometimes sharp, sometimes lazy, and sometimes just spinning.

Change up. Despite his limited fastball velocity, Tolleson was able to get decent separation with his change up but without much tumble or fade. The change up was rarely thrown, and right now, it's clearly his third pitch.

Mechanics. Take a look at the video below. A couple of things jump out right away. The most obvious for me is his inverted W.

In Tolleson's delivery, his inverted W leads to a really late forearm turnover and significant reverse forearm bounce. These arm actions put the ulnar collateral ligament at great risk. I am not surprised that he needed Tommy John surgery coming out of high school, and I believe that these mechanics are likely to lead to more elbow trouble down the road.

In the video, it is also quite clear that Tolleson strides toward the third base side. This establishes a drive line that is not directed at the target and requires the trunk and throwing shoulder to compensate by throwing across his body just to get the ball heading toward the catcher instead of the on-deck circle.

This compensation also leads to a violent follow-through where his humerus nearly collides with his face before flying down across his torso.

When his humerus nearly slams into his face, it is likely compressing the long head of the biceps brachii against the bony structures of the shoulder girdle. During deceleration, the biceps flexes and creates tension in its long head which attaches to the glenoid labrum. The tension is magnified by the compression, and when this tension is violent enough, it pulls on the labrum and can lead to fraying and tearing (SLAP lesions). This is not necessarily a problem in Tolleson's case; the 210 frames-per-second video doesn't slow down this part of his delivery well enough to draw a conclusion.

When Tolleson drives his arm across his body, his humerus is next to his right ear one moment and down across his torso the next. This is like whiplash for the supraspinatus muscle, the most frequently torn rotator cuff muscle in overhead-throwing athletes.

Overall. Tolleson is likely still trying to get all the way back from Tommy John surgery, but in this game, he looked less like an early round pick and more like a guy who could go undrafted. Based on his late season success last year, I think it's unlikely that he will continue to struggle, but if his struggles do continue, he could return to Baylor for his junior season.

He has several risk factors for future injury: inverted W, late forearm turnover, reverse forearm bounce, and throwing across his body. As a pitcher who has a significant injury in his past, his mechanics are definitely a concern going forward.

For me, Shawn Tolleson is a wait-and-see player. He has shown great potential in the past, and despite his struggles on this night, he was able to put together a quality start. If his stuff can return to its previous level, he could be worth taking a chance on.

Video scouting first look

Trip Somers • February 24, 2009 • Scouting

Here's a first look at some scouting video shot over the weekend. Shown here is a pitch thrown in the 3rd inning of Game 1 of Saturday's double header between UT Dallas and Texas Lutheran University. UT Dallas came back from being down 13-3 to win the game 14-13 with an 11-run 5th inning.

The pitcher in this video is UT Dallas starting pitcher Jonathan Reeder, a left-handed junior transfer from Eastfield College. UT Dallas is a 4-year Division III school, and Eastfield is a Division III junior college. Back in the winter of 2007-2008, I worked with Reeder on his delivery for a few bullpens - not enough time to officially consider him a student of mine, though.

You can clearly see his pronation, and for this pitch at least, his arm doesn't fly across his body during the follow through. Though he shows some late forearm turnover, the rest of his arm action is very healthy. I also think his back side could add a bit more energy and help drive his throwing shoulder with more power.

Since recording this video, I have found a couple of tweaks that will improve future video quality including a YouTube optimizer setting. The video here was recorded at 420 frames per second, so the motion detail is outstanding.

They won't be the sharpest videos you've seen, but they should get the job done.

The Magnus effect: why pitches move

Trip Somers • February 19, 2009 • Training

When a ball spins, it creates an envelope of air around it called the boundary layer. This boundary layer moves with the ball whether it spins forward or backward or sideways. The interaction of this boundary layer with the surrounding air results in an outside force that changes the path of the baseball. This is the Magnus effect.

Named for German scientist Heinrich Magnus, this effect is a principle of fluid dynamics that describes the lift created by the spin of an object that is moving through a fluid (gas or liquid).

To better understand lift, here is a brief look at how airplane wings create lift. The shape of airplane wings causes air to move faster over the top of the wings than it moves beneath the wings. The faster moving air results in lower air pressure above the wing and greater air pressure beneath the wing. The greater air pressure pushes the wing up; this is lift.


The spin of the ball dictates the rotation of the boundary layer. When the ball has back-spin, like a fastball, the boundary layer under the baseball shoots air forward into the air that is trying to move around the baseball. The opposing air flows result in slower air movement and higher air pressure underneath the baseball.

On top of the ball, the boundary layer shoots air backward in the same direction as the air that is trying to move around the baseball. These air flows compliment each other and combine to create faster air movement and lower air pressure on top of the baseball.

The combination of slower air movement under the ball and faster air movement over the ball creates lift that opposes gravity - a "rise". The Magnus effect, in this case, acts just like an airplane wing.

For a curveball, the top-spin is like turning that wing upside-down. The opposing air flows are now on top of the baseball, and the complimentary air flows are on bottom. Here, the Magnus effect creates lift that compliments gravity - a drop.

With a tilted spin axis, the Magnus effect creates a tilted lift. A left tilt adds right-to-left movement when the pitch has back-spin and left-to-right movement when the pitch has top-spin. A right tilt has the opposite effects.

When a pitch spins perfectly sideways, like a screwball or a sweeping curveball, the Magnus effect does not create a "rise" or drop. Instead, it creates sideways lift. Viewed from the top, clockwise spin results in left-to-right lift, and counter-clockwise spin results in right-to-left lift.

Curveball - Forward Spin
Curveball - RHP Perspective
Sweeping Curve - Side Spin
Sweeping Curveball - RHP Perspective
Screwball - Side Spin
Screwball - RHP Perspective


The Magnus effect is greatest when the ball's spin axis is perfectly perpendicular to the velocity of the baseball. As the spin axis turns (or yaws, if you're into that sort of thing) from perpendicular to parallel to the baseball's velocity, the Magnus effect decreases accordingly. Likewise, the magnitude of the Magnus effect increases as the spin axis moves from parallel to perpendicular to the baseball's velocity.


When the ball's spin axis is perfectly parallel to its velocity, the Magnus effect is null, barring crosswinds. In this case, the ball spins like a bullet - clockwise for righties and counter-clockwise for lefties when viewed from the pitcher's perspective - and no part of the boundary layer opposes or compliments the surrounding air flow.

A pitch with this spin is called a gyroball, and despite what was widely reported when Daisuke Matsuzaka came to the states, the null Magnus effect makes this the straightest pitch that can be thrown.

Wind tunnel studies have shown that this type of spin results in a smaller wake behind the ball. A smaller wake means less wind resistance which means a gyroball does not slow down as much as a fastball does on its way to the plate.


A slider is intended to have glove-side lift, but Pitch-f/x data suggests that sliders move less than any other commonly thrown pitch. On Pitch-f/x charts, sliders are usually grouped around or very near to the chart's origin where zero horizontal movement meets zero vertical movement. This suggests that most sliders spin like gyroballs. I tend to agree.

Good sliders, though, will have a spin that is somewhere between that of a curveball and that of a gyroball. Such spin will create the sliding movement and, depending on the degree of tilt, a varied amount of additional drop for the pitch.

Cut fastball

If a slider's spin is between that of a curveball and that of a gyroball, the spin of a cut fastball should be between that of a fastball and that of a gyroball. Where a slider ideally has some top-spin, a cut fastball has a large amount of back-spin.

The combination creates lift nearly identical to a fastball, but because the spin axis is turned slightly to the pitcher's glove-side, it also has glove-side run.

Split-finger fastball

Split-finger fastballs can be thrown with one of two different spins. The first spin is simply a slower back-spin than a normal fastball that creates less lift than a normal fastball would. When thrown at nearly the same speed as a normal fastball, the split-finger fastball appears to drop due to the smaller lift.

The second spin is actually top-spin. This is the ideal spin for an effective split-finger fastball because the forward tumble creates a drop like a curveball. The velocity of the pitch is similar to a fastball, but the spin is like a curveball albeit with a much slower rotation.

When top-spin is present in this pitch, it is sometimes called a forkball. A forkball is usually held with a deeper grip than a split-finger fastball, but the two pitches are practically identical give or take a couple of ticks on the radar gun.


Some sinkers spin like reverse-cut fastballs, and some sinkers spin like reverse-sliders. Most are somewhere in between. A power sinker, like the one thrown by Brandon Webb, spins almost like a screwball but with fastball velocity.

The same rules that apply to cut fastballs and sliders also apply to sinkers. The difference is that cut fastballs and sliders have glove-side lift while sinkers have arm-side lift.


The 108 stitches on a baseball grab the air around the ball and create a larger boundary layer than a ball with no seams would create. The horseshoe shape all around the baseball allows a pitcher to throw just about any pitch as a two-seam pitch, a four-seam pitch, or something that isn't quite either of those (a three seamer?). Most sliders fall into the third category.

A four-seam pitch spins on an axis that allows four seams to influence the boundary layer. The four seams are evenly spaced (balanced) around the baseball. This symmetry creates a stable and relatively predictable Magnus effect.

A two-seam pitch, though, spins on an axis that unbalances the seams even though all four seams still influence the boundary layer. This axis puts a seam loop on either side of the ball, leaving the two connecting seams close together on one side of the ball.

With the axis turned slightly to the left or the right, one of the seam loops moves toward the point of pressure (where the ball breaks through the surrounding air and experiences the greatest wind resistance), and the other seam loop moves away from it. This axis exaggerates the Magnus effect of the seam that moves toward the point of pressure, and reduces the Magnus effect of the seam that moves away.

The dominant seam, because of its almost circular shape, creates a point of nearly constant friction as it pushes boundary layer air almost directly into the air breaking across the point of pressure. When the seam catches that angle just right, the baseball will dart left or right depending on which seam is dominant.


I've talked a lot about how a pitch spins and why it moves the way it does, but I haven't yet touched on the magnitude of the Magnus effect. The obvious part is that greater movement is due to a greater Magnus effect. The not so obvious part is how to increase the Magnus effect to create even more movement. The simple answer is to give the ball more spin.

The faster a ball spins, the greater the resulting Magnus effect will be.  Squeezing just one extra rotation out of a pitch can have dramatic results on the pitch's movement.

You may have noticed that I didn't talk about the knuckle ball at all. Well, the knuckle ball doesn't spin, so it has no Magnus effect. A knuckle ball's movement is strictly an aerodynamics issue where the seams cause immediate disruption in the surrounding air flow rather than through a boundary layer. On the pitch's way to the plate, chaos theory takes over and the knuckle ball waivers as the seams catch air and unpredictably change the path of the ball.

Finally, release angles play a sizable role in creating "hidden" movement. For example, if a pitcher releases the ball two feet outside of the rubber, it has to move roughly 3 1/2 feet to reach the opposite corner of the plate.  Sliders and curveballs with glove-side lift will look like they are moving nearly 4 feet as they cross that corner, even though they only break about 3 to 5 inches.