A number of rookie pitchers toed the rubber last weekend. Trevor Bauer continued his personal battles with mechanical consistency  on his way to walking seven Rays (including the first four he faced), while Julio Teheran continued to struggle with his curveball. Shelby Miller had a successful introduction to 2013, building on his excellent showing down the stretch last season, though his heavy reliance on the fastball raises familiar questions as he gets deep into games.

The aforementioned pitchers had each entered spring training with a chance to win a spot in the rotation for their respective reams, and each player had already been exposed to the bright lights of the majors, but the most impressive rookie on display last weekend was a 20-year-old with zero experience above high-A who shocked the baseball world with his massive leap to the majors. Jose Fernandez made his major-league debut for the Marlins on Sunday, pitching in Miami less than two years after he had been selected in the first round of the 2011 draft out of a Florida high school. Fernandez stepped onto the field as the second-youngest player in a major-league uniform (that Bryce Harper guy is younger).

The decision to promote Fernandez is debatable (not that the Marlins are listening), but I was selfishly excited to see the young right-hander take the mound. It’s easy to root for a pitcher with such an incredible back story, but the tale of his development is nearly as fascinating. Fernandez was a raw talent when he came to the States, but he was taken under the wing of coach Orlando Chinea, who  helped to mold Fernandez into the pitcher he is today. Chinea was at the debut on Sunday, sitting with the rookie's parents in the Miami stands and offering insight into Fernandez’ background as a pitcher.


The box score made the first inning look easy, with Fernandez needing just eight pitches to retire the top of the Mets’ lineup in order. His velocity registered in the 93–96 mph range, but the right-hander was greeted with plenty of contact in the opening frame, exercising the outfielders with three consecutive flyouts. Fernandez leaned on the fastball early and often, starting with five straight heaters to start the game.

Ike Davis led off the second inning for the Mets, and Fernandez stuck to the gameplan by opening the at-bat with another fastball:

The pitcher's arm could not catch up to his body on this delivery, releasing the ball before reaching full extension and resulting in a pitch that missed the target high and to the arm side. The late arm was a common occurrence on Sunday, and Fernandez's fastball command fluctuated in the early going, trading well-located offerings with mistimed deliveries. Such inconsistency is to be expected for a young player, and the command profile was impressive for a pitcher his age.

Fernandez came back with this fastball on the second pitch to Davis, showing the same velocity but with improved timing, and getting some help from a strong frame by catcher Rob Brantly that encouraged a strike call from home-plate umpire Jim Wolf. The right-hander had thrown 10 pitches in the game thus far, eight of which came from the fastball bucket.

The above pitch was the first change-up of the day from Fernandez, and it invited an ugly swing from a surprised Davis. The change-up is considered the weakest pitch in the youngster's arsenal, and though he threw just a handful of off-speed pitches on the day, the early returns suggest that Hernandez's cambio has the potential to be a plus offering.

Many young players fall into the habit of either: A) burying their breaking pitches under the zone in an attempt to coax empty swings, or B) dropping a “show me” curve over the heart of the plate on 0-0 counts in the hope of catching hitters who are sitting on heat. It is rare to see a young pitcher with command of a pitch with such heavy break, but the 20-year-old Fernandez repeatedly demonstrated the ability to freeze batters with called strikes on breaking balls near the edges of the zone. Davis was the first such victim, and Brantly tossed the baseball into the dugout to commemorate the first strikeout of the young pitcher's career.

Once Fernandez had planted the seeds of his secondary stuff into the hitters' minds, he reverted back to his heat-centric ways for the rest of the inning, throwing 11 consecutive fastballs to the next two batters. Major-league hitters will often exploit such a blatant trend, but the Mets were repeatedly late on their swings due to Fernandez's killer combination of raw velocity and a deep release point.

Lucas Duda had seen four straight fastballs before the above pitch, after witnessing the previous batter get treated to six in a row, yet he was still unable to catch up with the 97-mph fastball of Fernandez. The trend continued into the third inning, and the string of fastballs reached 16 consecutive pitches at one point, until Anthony Recker was stunned by an 0-1 breaking ball at the knees.

Fernandez was perfect the first time through the lineup, leaning heavily on his fastball to the tune of 28 heaters out of 33 pitches across the first three innings. The first 10 hitters were greeted with first-pitch fastballs. He would change that tune on his second trip through the batting order, lowering his fastball frequency to approximately 50 percent, and every at-bat for the rest of the game would feature at least one non-fastball.

Daniel Murphy's fourth-inning single squelched the notion of a perfect afternoon for Fernandez, and it put the pitcher in the stretch for the first time. Unfazed, the rookie flummoxed David Wright with a three-pitch sequence that started and ended with sharp breaking stuff, and which quickly and efficiently sent the All-Star third baseman lumbering back to the dugout.

The sequence started with an 80-mph breaking ball that was well-located on the outer edge of the zone. It was the first time that Fernandez had started a batter off with the breaker, and Wright, who was likely geared up for a fastball, let it go.

Wright got his fastball on 0-1, aimed at a similar location as the previous breaking pitch, but the 15-mph jump in velocity produced a late swing and a harmless foul ball, setting up the 0-2 count.

Fernandez went right back to the breaker with two strikes, and rather than attempt to waste a pitch in the dirt, Fernandez dropped one over the plate that caught Wright looking for the called K. Brantly had set up outside, and though Fernandez missed his target location, the element of surprise was enough to keep the bat on Wright's shoulder.

The rookie issued his only walk of the day to the next batter, Davis, putting two on with two out for the first real scoring threat of the afternoon, but Fernandez extinguished the threat himself with a little PFP.

The young hurler avoided the slide step when pitching from the stretch, but he did shrink his leg lift with a runner on first base. He had no problem lining up the delivery versus Wright, and his first fastball from the stretch lit up the radar guns at 97 mph, but Fernandez otherwise struggled to find his top velocity when pitching with the compromised lift and a runner on first. He restored his regular lift with first base clear (even with a runner on second) and had no problem holding his velocity into the fifth inning, but the small sample of pitches with a runner on first base had an average fastball velocity that was 1.5 mph lower than with the cold corner empty.

The Mets would eventually plate a run in the fifth inning, thanks to a rare example of a hanging breaking ball that Collin Cowgill laced down the left-field line for an RBI double.

It was the third breaker of the four-pitch at-bat to Cowgill, and the drifting action of Brantly's catcher's mitt indicates the extent to which Fernandez missed the target.

Fernandez completed five full innings in just 80 pitches, allowing three hits and the one walk, and his eight strikeouts broke the team record for a debut performance. The rookie exited with a 3-1 lead, but closer Steve Cishek would blow the save in the bottom of the ninth, robbing Fernandez of the big W and costing the Marlins the game.

Mechanics Report Card









Release Distance




The grades on his mechanics report card would be great for a five-year veteran of the big leagues, but such high levels of mechanical efficiency are virtually unheard of for such a young pitcher. He has quieted the drop-and-drive portion of his delivery, with balance that has greatly improved during the phase from leg lift to foot strike, though he occasionally struggles to maintain balance during the high-energy phases of rotation. His posture varies between average and plus, with relatively little spine-tilt, and he has the foundational components to keep improving.

Fernandez has excellent momentum that allows him to recruit kinetic energy from his lower body, and though he flashes a 65-grade on his momentum from time to time, such a pace typically puts him into foot strike too early, and his ideal timing and stride appear to be linked to a momentum grade of 60. His high-90s heat is derived from excellent torque, generated by equal doses of upper-body load and a strong delay of trunk rotation after foot strike.

It all adds up to excellent depth at release point, particularly when Fernandez finds his ideal extension, allowing his high-90s fastball to play up even higher. Major-league hitters can hit any fastball if they get a long enough look at the ball due to a shallow release, but pitchers such as Fernandez can be devastating due to the shrunken window of opportunity for batters to identify the incoming pitch. The resulting increase in perceived velocity can make his 97-mph heat appear to be cracking triple digits. The depth at release point helps to explain why Fernandez was able to generate so many late swings from big-league hitters who essentially knew that a fastball was coming.

The grade for repetition might appear to be the weak link in his chain, but consistency of timing is the last thing to come around for the vast majority of pitchers, and it is incredible to see a 20-year-old with such composure on the biggest stage, with the adrenaline pumping and the television cameras studying his every move on the mound. Fernandez has made tremendous improvements to his delivery in the last couple of years, and though I was shocked when I first witnessed the great mechanical changes that the right-hander has made, the picture became clearer during the in-game interview with coach Chinea, when he dropped a special thanks to my NPA mentor, Tom House.

One of the great anecdotes that Chinea retold was about Fernandez’s affinity for shaking off his catcher, and his desire to play the chess match with opposing hitters. This frequent head-shaking was on full display in his major-league debut, and one can imagine the patience required of rookie catcher Rob Brantly:

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Great read.

Is his tendency to sit on that back leg contributing to the late arm? It's not the worst thing in the world, the way he does it, but that definitely stalls his momentum a bit in his windup mechanics, and it seems like his front side is headed downhill and opening before his arm can really get going. He looked better from the stretch, to me, because he didn't overlift the front leg the way he does from the wind and he rode his back leg downhill better.

Is any of that right?

Thanks as always, Doug.
The "sit" used to be much worse, with an exaggerated drop n' drive, so this is an improvement. If anything, he often gets into foot strike too quickly from the windup due to outstanding momentum, which is a good thing except when it throws off a pitcher's timing, and the "sit" could actually be helping to find that ideal timing by slightly delaying his charge. His momentum was volatile on Sunday, and the ones where he missed up and to the arm-side were tied to those pitches with the fastest pace.

He also struggled to line things up from the stretch with a runner on first, as the truncated leg lift got him into foot strike too quickly, again producing a late arm. I think that it all boils down to consistency, and finding an ideal pace to the plate that lines up the gears of his delivery.
Also, I think you're on to something with the "sit," as when Fernandez exaggerates that stall then it delays the upper-body portion of rotation, causing the arm to trigger late.

You can see this in the first two GIF's. The "sit" is more obvious in the first GIF, and he triggers trunk rotation too late. The second GIF has better momentum but also less "sit," and he has no problem with his timing of trigger.

Great stuff as usual, Matt!
This is one of the best articles I've ever read on BP. Kudos, Doug.
Painstaking analysis...thanks.
(Daniel Murphy, not David)
I make that mistake every stinkin' time!
quality work. thanks doug
Thanks Doug, Great Read,