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Yaisel Sierra, RHP, Los Angeles Dodgers (High-A Rancho Cucamonga)
The Dodgers kept their $30 million man in extended spring training to start the season before transferring the 24-year-old to Rancho for his professional debut on Saturday. His first taste of competition in a couple years featured plenty of rust. His slender, athletic frame is on the smaller side, and while his movements were easy, he struggled to repeat his delivery and find his release point for most of the night.
The motion is low-octane, with a fluid takeaway into a clean arm swing, and he showed above-average arm speed. Most of his problems on this night stemmed from a poor drive: he didn’t leverage his weight particularly well, staying uphill as he pushed forward and failing to fire his hips. That created drag to his release point and a wildly inconsistent finish with his lower half.
Stuff-wise he came out 91-93 with the fastball, twice touching 94 in the first inning, before largely settling into a narrower 91-92 range. The pitch sinks and runs a bit, with life and some weight to get under barrels (or miss them entirely). He struggled mightily to harness it from the jump, missing constantly to his arm side. He leaned heavily on a slider that he toggled between 81 and 85, with a softer, rounded shape at the lower end of the band when he worked it in the zone. He doubled- and tripled-up repeatedly, frequently back-dooring it and stealing strikes, though predictability led to trouble after he’d gone through the order once. At its top velocity it played much tighter, with late bite and hard vertical action, and he deployed it as a chase pitch below the zone whenever he got ahead. He threw a couple 88 mph changeups with split action, but overwhelmingly this was a two-pitch effort. Sierra induced 10 swings and misses en route to punching out seven hitters in his four innings, but it took him 81 pitches to get there, and he and catcher Julian Leon struggled to get on the same page throughout, leading to a labored pace.
There were glimpses of the potential that lead to his big contract in this start, but if the outing was indicative of where he’s at, there remains an awful lot of work ahead of him before he’s going to be helping the big club. -Wilson Karaman
Edwin Diaz, RHP, Seattle Mariners (Double-A Jackson)
With 35 strikeouts and just five walks in his first 30 innings across five outings, Diaz is off to a terrific start in his second spin through Double-A. He works with a low-to-mid-90s fastball and an improved slider that flashes plus. His changeup remains fringy (and a developmental goal throughout the rest of the season) but he’s grown as a starter this season. His command has improved, as he’s demonstrated an ability to move the fastball around the strike zone.
Perhaps the biggest knock on Diaz’s projection is durability. Listed at 6-foot-3 and 165 pounds, he could generously be described as slender, and between his build and a high-effort delivery, evaluators have long questioned whether he’ll be able to carry a starter’s workload. He’s tamed his motion a bit this year—which helps with his command and should ease concerns about wear and tear—but he’s also only exceeded 90 pitches once so far. That’ll be something to monitor as the weather warms, because it’s looking more and more like he’ll at break into the majors as a starter. -Brendan Gawlowski
Ozhaino Albies, SS, Atlanta Braves (Triple-A Gwinnett)
Albies has been exceptionally young for every level, skipping the Carolina League entirely and not once facing a pitcher younger than him in three seasons. Making his Southern League debut in his age-19 season—he won’t turn 20 until January—Albies more than met the challenge with a .369 average and .954 OPS in 22 games. It’s certainly a small sample size, though the Braves planned to promote him in tandem with Dansby Swanson in May and his bat showed no signs of going cold anytime soon.
Albies is mature beyond his years with an advanced approach, recognizing pitches well and hitting to all fields from both sides of the plate. He makes solid contact to the opposite field but also made the adjustment early this year to pull the ball from the left-hand side. Albies has never hit for much power and playing in the homer-adverse Trustmark Park didn’t help, but the expansive outfield played to his strengths both at the plate and on the bases. He’s an instinctual shortstop with a plus arm, quick first step and good range. He’s also level-headed with an ability to slow the game down and make in-game adjustments.
Either Albies or Swanson will move to second base in the majors, though Atlanta split them up for now to give them equal playing time at shortstop. With the exception of nine spring training games, Albies hasn’t played anywhere else in his pro career. The Braves have a big decision ahead, albeit one they shouldn’t make until September at the absolute earliest. -Kourage Kundahl
Oscar Mercado, SS, St. Louis Cardinals (High-A Palm Beach)
It was a rough weekend for the Cardinals’ 2013 second-round pick, who went 0-4 in Friday’s game and rode the pine in Saturday’s matchup. Mercado is off to a characteristic poor start to his season, hitting just .211/.307/.276 through 88 PA. The bat has never been Mercado’s carrying tool, but he has proved capable of making adjustments, and a strong showing at the plate last August boosted Mercado to High-A to begin the year. Slim and undersized, Mercado struggles to drive the ball, but is able to make regular contact, and his better at-bats feature deep counts and a number of foul balls. The 6-foot-2, 175-pound shortstop will be successful if he can make pitchers work and refine his line-drive approach. Still only 21, Mercado has time to improve his swing and plate vision, and even if the power never arrives (I wouldn’t bet on it), it’s reasonable to expect modest improvement in the walk rate and batting average as he learns to be more selective at the dish.
That deflating opening paragraph aside, Mercado can make an impact with his glove and speed. He currently leads the FSL in stolen bases with 12, and swiped 50 in Low-A Peoria last season. The speed is easy plus, and Mercado will impress with his instincts and IQ on the basepaths. His quick-twitch speed also plays in the field, where he excels at reaching balls at the fringe of his range. He should have no trouble staying at shortstop, where his athleticism and fluidity contribute to impact plays. Although Mercado seems unlikely to be a first-division regular, he could be the next Cardinals half-prospect to make a surprising impact upon a call-up, a la Aledmys Diaz. -Will Haines
Dietrich Enns, LHP, New York Yankees (Double-A Trenton)
What if I told you that the pitcher with the lowest ERA in the minor leagues in 2015 (minimum 50 innings) had yet to allow a run in 2016, and carried no-hitters into the sixth in both of his two most recent starts? What if I told you he was a lefty striking out 9.5 per nine innings in a Double-A rotation this year and 9.7 per nine for his career? What if I told you he had a pretty good fastball at 89-93 with movement, and flashed three major-league-quality secondary pitches?
Meet Dietrich Enns, the latest in a long line of underrated arms on the Yankees farm, just starting to get somepublicity. I’ve caught two of Enns’ starts this year in Trenton, and it’s hard not to like what you see, at least for the first four or five innings. Of the secondary offerings, Enns’ slider is most consistent, already a fringe-average pitch that he’s able to command well and, combined with his fastball, gives him a very good shot at some sort of major-league future by itself. Enns’ curveball has flashed as a potential future plus offering, with big break down in the zone and tighter spin than you often see in similar profiles, but is too inconsistent at present. It could end up being his best pitch, and it could end up being scrapped in Triple-A in favor of the slider. The change also shows promise; at its best, Enns gets quality fade down and arm-side, and even when it’s a bit firmer and straighter, it still has value as a show-me pitch.
So why haven’t we heard more about Dietrich Enns? He had Tommy John surgery in the summer of 2014, costing him over a year of development. Because of that, he’s now on the older side for a legitimate prospect at his level, turning 25 in two weeks. Before having Tommy John, he was mostly used a reliever in both college and the pros. Coming off surgery, Enns was left off the Yankees 40-man roster and went unpicked in the Rule 5 draft this past offseason. In both starts I’ve seen this year, he has noticeably tired in the fifth and sixth innings, and box scores of his other two starts suggest similar. His command—which in early innings has been a significant strength—has imploded once he hit the wall, with usual telltale signs like a dropping arm slot and inconsistent release point. Enns has walked nearly a batter per nine in the fifth inning and on so far this season, inflating his overall walk rate to 4.9 per nine for the season. These early-season struggles could be a product of Enns building stamina as a starter and post-Tommy John, or it could portend a future back in the bullpen.
Caveats and warts aside, Enns profiles as a major-league lefty specialist already, with upside beyond that. With further refinement of his secondary pitches and gains in stamina and command, I won't be surprised at all if he's holding down a spot in the middle of the Yankees rotation in a year or two. -Jarrett Seidler
Cam Gibson, OF, Detroit Tigers (Low-A West Michigan)
Entering the organization as the fifth-round selection in 2015, Gibson divided his debut season between the Gulf Coast League and Short-Season Connecticut, hitting .248/.301/.454 with five triples, six home runs, and 27 RBI. Kirk’s son, Cam lacks the physicality of his father, and looks to be a top-of-the-order type of hitter, using his legs for hits more than driving the ball.
Speed is the calling card on both offense and defense for Gibson. With his first full month with Low-A West Michigan almost complete, Gibson boasts impressive range, moving lightly on his feet to cover a lot of ground in the outfield, though his range is effectively weakened by below-average arm strength. Offensively, he has the ability to clear the wall, but the label of a power hitter may be a bit premature. Gibson uses a wide leg stance, with most of the pop coming from his plus bat speed rather than an involved lower half. At 22 years old, projection is no longer a focus, but ingrained instincts and athleticism, combined with the skill of adaptation could work in favor of the center fielder sooner rather than later. -Emily Waldon
Tyrell Jenkins, RHP, Atlanta Braves (Triple-A Gwinnett)
Jenkins might have been the second piece in the Jason Heyward/Shelby Miller swap, but he was not a mere toss in. He could have been described as a lottery ticket type, but only because he was coming off of shoulder surgery, which is a red flag for many. The Braves haven’t been afraid to pick up pitchers with past injuries, and took the chance on Jenkins.
Since the trade, Jenkins has impressed the Braves brass. His fastball sits 90-93, and he showed the ability to bump his fastball as high as 96 against Toledo. He throws both two- and four-seam fastballs, which gives him more options. The two-seamer features nice arm-side run that complements the higher-velocity four-seam well. The command isn’t quite there yet, as he struggles to hit his spots consistently. His delivery has an easy motion to it; a loose throwing motion that generates easy velocity.
His secondary pitches also lack consistency, as his hard curveball will sit around 78-80 with nice, late break but he misses his spots with it too often. Jenkins is comfortable throwing his breaker to lefties or righties, in part because he lacks confidence in his changeup. His change sits at 83 and shows arm-side fade, but he needs more reps with the pitch. He has the making of a mid-rotation starter with his plus fastball, and potentially plus breaking ball, but needs to work on the changeup significantly. If he can do that, improve his command, and avoid the injury bug, he will be a welcomed addition to Atlanta. -Grant Jones
Yimmi Brasoban, RHP, San Diego Padres (High-A Lake Elsinore)
Brasoban was a name I wasn’t terribly familiar with coming into the season—which is a nice way of saying I’d never heard of him—but he’s been one of the most impressive relievers I’ve seen in the California League so far, which is is also a nice way of saying that Lake Elsinore’s starting rotation isn’t very good.
Signed for $75,000 five years ago, Brasoban has impressive arm strength, and can get his lively fastball into the high 90s; typically 94-96. His slider isn’t a Mr. Snappy, but it’s pretty good. It’s got late tilt and is difficult to pick up out of his arm slot. If you can pick up, don’t swing, as he hasn’t thrown a strike with it in my viewings, but that’s easier said than done. He’s also thrown a split-like change, but that should be scrapped against righties and used rarely against southpaws. It’s strictly a show-me pitch.
Relievers aren’t the sexiest profiles, but they’re people too, dang it, and Brasoban has the stuff to potentially be a high-leverage arm if he can start to locate the slide-piece for strikes. If not, he can be a nice little “death to righties” part of someone’s bullpen in the next two to three years. -Christopher Crawford
Francisco Rios, RHP, Toronto Blue Jays (Low-A Lansing)
Signed in 2013 by the Blue Jays, Rios made it to Low-A Lansing quickly. The 20-year-old, right-handed starter has a medium-sized, physically mature frame. He starts from a semi-windup and a high-three-quarters slot. On the back side there is a small stab at his max swing along with a slight pause at max leg lift. Out front he lands on-line with a stiff front leg but gets through it well most of the time.
His fastball sits 89-92 mph, touching 93, with slight arm-side run, especially when down in the zone. There is deception on the fastball with many awkward swings, weak contact, and I witnessed ten swings and misses, helping the fastball play closer to average instead of a grade below. The ball gets on hitters quickly because they struggle to pick it up out of his hand. He locates the pitch to both sides of the plate, while most misses were to his glove side. The slider is Rios' main off-speed offering with short 11/5 shape and he flashed average rotation at times. It sat 81-83, and hitters struggled recognizing the pitch out of his hand. He also threw a handful of curveballs but it was more of a show-me pitch than a weapon. The curve lacked quality rotation and he just flipped it into the zone. His straight change sat 85-86, with some drop, but he lacked consistent arm speed. It is a work in progress at this point.
Rios has the makings of a back end of the rotation starter but lacks a true third pitch at present. He gets hitters out with his fastball/slider pairing, combined with deception that keeps hitters off balance and throws enough strikes to stay a starter for now. If the third pitch doesn't come, Rios could be a weapon out of the pen, especially if the velocity plays up. -James Fisher
Amed Rosario, SS, New York Mets (High-A St. Lucie)
After catching four games in the first month of the season, I can say that Rosario is not only the best player on his team, but one of the best in the Florida State league. The 20-year-old, defensively gifted Rosario checks in at 6-foot-2, 190 pounds, up from the rail thin 170 he’s listed at, which he says he gained from his offseason workouts. As many evaluators have noted, the plus glove and the arm have always been there.
One month into the season, Rosario has not only been a plus performer on defense, but his offensive skills seem to have gained ground on the glove and arm. Rosario has a .305/.340/.537 slash line, good for a .877 OPS. He is currently leading his team, and among the league leaders in triples (5), home runs (3), and OPS. He has been hitting balls to both gaps with power, showing plus bat speed. His ability to spray the ball all over the field has helped him to lead the FSL with 51 total bases. His manager, Luis Rojas, praised his strike-zone discipline and ability to cut down on strike outs. Rojas went on to say that Rosario “comes to plate with plan,” which is a sure sign of his offensive maturation.
Rosario’s bright future is seemingly reaffirmed following his April performance. Even before Rosario’s recent offensive growth, his promotion to Binghamton appeared to be just a matter of time given the Mets aggressiveness with him. The two shortstops occupying that space now won’t be a deterrence, nor will waiting until the half season mark and/or the weather to warm in Binghamton, New York. -Thomas Desmidt