The “Bush League” series kicked off last week with a review of the top two picks of the 2011 draft, Gerrit Cole and Danny Hultzen. This week's edition continues down that historic '11 draft board with a close look at Trevor Bauer, the second UCLA Bruin chosen among those first three picks and the first player from the arm-laden first round to crack the majors.

From the standpoint of a pitching addict, Bauer is one of the more intriguing prospects to come around in quite a while. His appreciation for biomechanics, his commitment to conditioning and physical preparation, and his cerebral approach to his craft are rare qualities to find in a 21-year-old hurler. One need only glance at Bauer's Twitter feed to understand that this is a unique mind on the mound, one whose scientific approach to the game raises the roof of his potential. However, such attention to detail can also be the undoing of a pitcher who can't get out of his own head, placing him at risk of becoming his own worst enemy on the mound.





























Bauer went through stretches of dominance and ineffectiveness alike this season, running up high pitch counts in Reno and Arizona, though such environments are hardly conducive to quick innings. Triple-A Reno features a notoriously brutal park for pitchers, and road assignments in Tucson and Colorado Springs can wreak havoc on a pitcher's stat-line, providing the context that underscores the relative brilliance behind Bauer's Triple-A run prevention. His K rate was excellent in his first year of pro ball, but walks were an issue, as his volatile delivery is exceptionally difficult to coordinate consistently. He showed signs of improvement in his last three starts of the minor-league  season, posting just four walks against 26 strikeouts across 22 innings of work. The sudden rush of command was fleeting, and though Bauer put his team in a position to win each of the three playoff games he started, the 17 walks he allowed in 16 1/3 postseason innings are indicative of his battles with finding a release point.

Bauer started the final game of the minor-league season when he toed the rubber for the Reno Aces in the Triple-A championship against Pawtucket on September 18th. The young right-hander would lead his teammates to a convincing 10-3 victory, though his continued problems with pitch command would lead to an early exit that left Bauer just a single out shy of recording the official W. He gave up a pair of earned runs during his four-plus innings of work, but a season-high seven walks contributed to a pitch count that cracked the century mark before he could close out the fifth. 

Bauer was never in danger of earning the L, cruising through the first couple frames while his teammates repeatedly plated runs. The Aces held an eight-run advantage by the fourth inning, when the PawSox coaxed their first run via a bases-loaded walk, Bauer's third free pass of the inning. Bauer battled his timing for most of the outing, throwing just 49 strikes out of his 101 pitches, and his delivery unraveled at times in the middle innings.

If there was one plate appearance that summarized the day for Bauer, it was Danny Valencia's at-bat to lead off the fourth inning, in which the righty ran the command spectrum from painted targets to wayward projectiles. The first pitch set the tone with notes of chin music as Valencia flinched in avoidance.

Bauer was able to regain his timing and come back with a pair of painted targets on the next two pitches, locating his off-speed stuff to keep Valencia off-balance.

Just as it appeared that Bauer had found his ideal time signature, the delivery fell off-track. His fourth pitch to Valencia was a breaking ball that behaved like a lawn dart, bouncing a few feet in front of the plate thanks to a slow delivery and a bad case of over-rotation. Bauer would miss his mark with each of the next two pitches, with the only fastball of the at-bat coming on a 3-2 pitch that resulted in a walk.

In all fairness, Bauer was at the tail-end of a long season and he was riding a substantial lead throughout the game, extenuating circumstances that could have played a role in his overall performance. That said, his pitch efficiency came into question multiple times this season, and his relentless quest for the punchout was on full display in the Triple-A Championship. Ten of the first 11 batters required four or more pitches to complete the at-bat, and Bauer's pitch count per inning increased steadily throughout the game. Though he was plagued by inconsistent command, Bauer's go-to pitch was an 80-mph changeup that he could trust to find leather.

His changeup was his most consistent offering, but it was the curveball that Bauer increasingly favored as he churned through the lineup. With a repertoire that includes multiple sliders in addition to the curve, his pitches are distinguished more by the shape and depth of break than a spread of velocity, as his breaking stuff and his cambio register within the narrow range of 78-82 mph on the radar gun. He also throws a signature pitch that he calls a “reverse slider” and which Gameday recognizes as a mid-80s screwball due to tremendous arm-side run. Bauer's four-seam fastball sat in the 89- to 91-mph zone for most of the contest, and the hardest-hit baseballs of the afternoon all came on the heat, including this home run by Tony Thomas to lead off the fifth inning:

Mechanics Report Card









Release Distance




Bauer's extreme delivery comes with steep peaks and valleys on his mechanics report card, with poor marks often coming down to personal philosophy on pitching mechanics, as the right-hander is very cognizant of his actions on the mound. Bauer has drawn persistent comparisons to Tim Lincecum, due to a “Freakish” motion inspired by the two-time Cy Young Award winner. Bauer's Lincecum-like appreciation of linear momentum is particularly evident when he is pitching from the windup, as he takes a step backward before he propels himself down the slope.

His potent charge to the plate enables Bauer to find a deep release point, allowing him to increase perceived velocity as well as disguise his secondary pitches with late movement. The student of the game has been well-trained in the multiple dimensions of velo, including real velocity, perceived velocity, and even effective velocity. The grades reflect his appreciation of momentum as well as high levels of torque, both of which combine to increase the effectiveness of his four-seamer. Bauer has distinct isolation of hips and shoulders in creating separation, allowing the hips to rotate before triggering the shoulder axis into trunk rotation.

Despite Bauer's attention to mechanical detail, it appears that he has overlooked the critical role of dynamic balance in pitch execution, instigating considerable head movement throughout his delivery. Bauer fails to keep his head over his center of mass in the early phases of his motion, and he exhibits a severe drop-and-drive that artificially lowers his center of gravity as he approaches foot strike. His postural stabilization also suffers from heavy spine-tilt as he finds an over-the-top arm slot, with considerable glove-side head-movement into release point. The lack of balance is an underlying component of Bauer's struggles with pitch command, hampering his ability to repeat the delivery.

The other areas of inefficiency in Bauer's motion have to do with consistency of timing, particularly as he adjusts from the windup to the stretch. The back-step that Bauer employs from the windup necessarily disappears with runners on base, and that change in strategy results in reduced momentum from the stretch position, as Bauer is unable to find the same level of propulsion that he can achieve from the windup. He gets the momentum charged early in the sequence when pitching with the bases empty, but from the stretch he appears to wait until after maximum leg lift before he initiates the burst toward the plate. The adjustment creates disparate timing patterns that further disrupt his ability to find a consistent release point. 

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With the role that maximum leg-lift plays in creating momentum out of the wind-up, how should a pitcher best maximize momentum out of the stretch?

I would assume that using maximum leg lift would be ideal, but how can a pitcher compensate for that momentum when using a slide step? Professional pitchers don't, to my knowledge, sacrifice significant velocity in switching to a slide step--or do they?

Thanks for the article! Love this stuff.
A big leg-lift can aid momentum, but more critically it allows a pitcher to get the most out of his momentum by allowing him to extend his stride and thus his release distance.

I am not a fan of the slide step for exactly this reason, and I prefer that a pitcher uses his natural leg lift from the stretch.

However, because many pitchers have poor early momentum (slow into max lift) from the windup, they will often have a better burst with a slide step in comparison, because they will get their energy moving toward the target from the get-go.
Nice writeup! But wow all his mechanic grades either as plus or more, or else awful, with nothing in between.
In your opinion, how would you rank hultzen, cole and Bauer's mechanics in terms of least likely to lead to injury.