Raising Aces: Shelby Miller’s Fall From Grace

At this time last year, the National League was being steamrolled by a young Cardinal right-hander whose mid-90s gas and hard-breaking curveball led the way to a 2.79 ERA as the calendar flipped to August. The instant success of Shelby Miller put him on the short list of the game's future kings of the hill, but he faded down the stretch and the Cards kept him out of the rotation (and essentially off the mound) during their postseason run; his lone appearance was a one-inning stint in game two of the NLDS, coming in the eighth inning of a 7–1 ballgame.

It was widely presumed that Miller had simply run out of gas at the end of his longest season as a pro, succumbing to the physical demands of a career-high workload. Expectations were high entering 2014, with a full offseason of rest and a year of experience under his belt, but this season has been a continuous struggle. His woes reached rock bottom in the last couple of weeks, resulting in his being jettisoned to the bullpen; even his initial foray in relief work left much to be desired, with two hits and a walk allowed in his first frame out of the 'pen. In hindsight, Miller has been on a downward spiral since the end of 2013, tainting what had been a very promising introduction to the big leagues.

	GS	IP	ERA	K %	BB %	H %	HR %
2013	31	173.3	3.06	23.4%	7.9%	21.1%	2.8%
2014	19	110.0	4.25	15.2%	11.5%	22.5%	2.5%

Miller's batted-ball profile from this season is in line with his performance from 2013. What stands out are strike-zone indicators, which are trending in the wrong direction. Miller is striking out hitters at just 65 percent the frequency of last season and issuing walks at a nearly 50 percent higher clip, causing his strikeout-to-walk ratio to tumble from a three-to-one pace last season to his four-to-three proportion of 2014. Controlling the strike zone has been an issue for Miller all season; even in a three-start stretch from April in which he allowed just one run across the trio of games, the Miller bequeathed 12 free passes across 17 frames.

Trajectory and Movement – from 01/01/2014 to 01/01/2015

The raw components of Miller's stuff are still there, with average fastball velocity that is within a rounding error of last season's speed as well as a nearly identical distribution of his typical two-pitch approach. Miller rarely deviates from the fastball-curveball combo, splicing in the occasional cutter to right-handed batters and mixing in some changeups to lefties. The lack of variation in his repertoire makes it easier for opposing hitters to sit on the fastball, but Miller helps to disguise his intentions by avoiding any specific tendencies in particular counts, a trait for which Yadier Molina deserves some of the praise. Miller's pitch-sequencing does not appear to have changed much (if at all) since last season, but the low-quality of his change leaves Miller highly-susceptible to batters who have the platoon advantage.

From my perspective, the biggest difference for Miller this season has been fastball command. The ability to hit targets with a fastball is the greatest skill that a pitcher can possess, and in Miller's case it bears added importance due to his heavy reliance on the pitch. His fastball command was excellent last season, and he was especially adept at hitting targets on the lower shelf of the strike zone, but that laser-like precision has disappeared in 2014. The right-hander has shown a tendency to find the middle-third of the strike zone in both seasons of his MLB career, but he has been unable to offset those mistake pitches with painted targets on the edges of the strike zone the way that he did in '13.

The fastball has long been Miller's go-to pitch for the strikeout, but in 2014 it has been virtually his only option. The curve has not been sharp, having resulted in more walks than strikeouts this season and with just seven plate appearances that ended with a punchout on the hammer. Batters are swinging less often at the curve in 2014 and they are enjoying much better results when they do choose to swing, with fewer whiffs and better results on batted balls, including a BABIP of .389. Miller clearly lacks confidence in the pitch, reducing him to a one-trick pony in clutch situations due to his lack of trust in the secondaries.

Mechanics Report Card

For an explanation on the grading system for pitching mechanics, please consult this pair of articles.

Power: The power grades remain virtually unchanged for Miller. His torque still earns a score of 65 on the 20-80 scale, with delayed trunk rotation that effectively takes advantage of hip-shoulder separation to derive fastball velocities that scrape 97 mph at peak. He has also retained above-average momentum, with a strong pace to the plate that utilizes his lower half to generate kinetic energy, allowing him to creep closer to the plate as well as add power to the delivery. The only real change to his power generation is that Miller has fallen off track with respect to his line of energy toward the target, as stability issues have caused him to frequently drift off-course this season; rather than finishing with a step toward the plate after release point, Miller is typically spinning off to the first-base side with an inefficient energy pathway.

Stability: Balance was a problem for Miller last year, with a pronounced drop of his center-of-gravity after max leg lift as well as a tendency to hunch over his front side during the stride phase. His balance has fallen further off the wagon this season, adding an element of lateral movement near the end of his delivery while simultaneously exaggerating his transition from spine hyperextension to flexion. This head-butting move is so pronounced this year that Miller sometimes looks like his head is going to hit the mound during his follow-through, and though most of the best pitchers use some degree of flexion in their deliveries, Miller has amplified the issue to the extent that it is wreaking havoc on his release point. On the vast majority of his pitches, the right-hander finishes imbalanced out in front as well as to the glove-side, elements that have tarnished his posture and thrown a major barrier in front of his ability to find a consistent release point, causing his repetition grade to plummet far below average.

When a pitcher's command is off-kilter, the solution is typically tied to mechanics, and Miller is no exception. The lack of stability and the inefficient transfer of energy form the basis of his command issues this season. He is shakier than last season when looking at the delivery prior to foot strike, but the real problems occur after the front foot hits the ground, as the lateral spin-off and the forceful flexion have wrecked his ability to reach ideal extension with a repeatable release point.

Such issues are likely tied to the back stiffness that Miller experienced earlier in the year, and the causation arrow could very well lead from the exaggerated flexion toward the physical ailments that he experienced. He may have to tone down the power in order to rediscover his stability and repetition; only when he has honed the balance elements of his motion does it make sense for him to again turn up the dials of power. Most of his inefficiency occurs during the late, high-energy phases of the delivery, and the good news is that it is easier for a pitcher to fix mechanical issues near release point than to start from scratch at the start of the delivery. Whether Miller can make that adjustment in-season remains to be seen.