Hidden Gems on the Farm: The Arms

Before this year’s minor league season begins, one of the commenters here at LSB had suggested what appeared to be a fun exercise. The idea was simple: dive into the farm system and see if you can dig up any under-the-radar names to keep an eye on this year. With the wealth of depth in the Rangers’ present MiLB system, identifying potential gems that have been concealed because they were either late-round selections, or were paid low international signing bonuses shouldn’t be too tough.

Before we dive into any actual analysis on a few dudes, let’s set a few ground rules to determine the pool of eligible players for this list:

1. Players must be age 22, or younger, on or before 4 May 2021 (Sorry, Cole Uvila)
2. Players cannot have previously received an assignment above A+ ball (Bye Bye, Blake Bass)
3. Players cannot be listed on MLB Pipeline’s 2021 Rangers Top 30 Prospects List (Ronny Henriquez, who was once a hidden gem, is now #16 on MLB Pipeline’s Rangers Top 30)

With the rules established, let’s first look at a topic that brings me outside of my comfort zone — pitchers. Within the regulatory framework of this exercise I’m particularly excited to get eyes on the following four unheralded pitchers in 2021:

Dane Acker

Alongside promising prospects Owen White and Tekoah “TK” Roby, who both would have undoubtedly made this list if they were not listed as the #17 and #24 prospects on MLB Pipeline's Rangers Top 30, Dane Acker will make his full season debut with the low-A Down East Wood Ducks. That rotation’s going to be salty, and while the Wood Ducks’ offense does not feature much outside of Evan Carter, Keithron Moss, and Luisangel Acuña, the team certainly looks well-positioned to defend its 2019 division title.

At 6’ 2” and 189 pounds, Acker’s body could accommodate some weight, but there’s not a ton of projectability left in the frame. While Acker (2020: 9.8 K/9, 1.8 BB/9, 0.7 HR/9, 0.77 WHIP) didn’t put up Jack Leiter (2021: 15.2 K/9, 3.7 BB/9, 0.9 HR/9, 0.79 WHIP) or Kumar Rocker (2021: 12.5 K/9, 2.1 BB/9, 0.4 HR/9, 0.73 WHIP) stats in his final collegiate season, he was well worth Oakland’s 2020 fourth round selection. If you want to get a solid impression of how Acker performed at the University of Oklahoma, look no further than his no hitter against LSU. Here’s all 27 outs of that performance:

Acker was shipped back to his home state of Texas as the supposed throw-in of the Elvis Andrus trade. The relative indifference towards his inclusion in the trade, at the time the deal was made, largely explains why I included him on this list. He doesn’t have an ace’s profile, but the man knows how to pitch.

Acker has five pitches in his arsenal: four-seam and two-seam fastballs, a curveball, a slider, and a recently developed changeup. The 2-seamer is arguably his best pitch, measuring consistently in the 91 - 94mph range. The 2-seamer also features significant horizontal and vertical movement. Acker deploys his 4-seamer sparingly, but uses it most often to run up-and-in against opposing batters. The 4-seamer is an average offering, but with plenty of spin appears more lively than it actually is. The gif shown below shows Acker painting with the 2-seamer. It’s got significant arm-side run, which brings it back into the zone:

On top of the fastballs, Acker’s curveball and changeup have 50-grades and have solid movement. The slider is a rough offering that needs further development. At present, the slider looks more like a slow cutter than anything, so Acker may eventually abandon it in favor of using the curve and change to play off his fastballs. Acker’s delivery is exciting. It’s easily repeatable, mechanically efficient, and does not present any injury flags. He’s going to be a durable innings eater, profiling well as a potential BORP.

Destin Dotson

Selected with the 359th overall pick of the 2018 MLB draft, it’s a miracle the 6’ 7” 230 pound then 17 year-old abandoned his commitment to Tulane to sign with Texas. Dotson’s $300,000 signing bonus, which was $175K over-slot for a pick made after the 10th round, surely played an outsized role in that decision to sign. One of the primary reasons the Rangers were willing to go so far over-slot to sign Dotson was his low-to-mid 90s fastball, with excellent spin to boot. Here, he uses each of his fastball, curveball, and finally his changeup to induce weak contact against White Sox prospect Josue Guerrero.

Coming out of a high arm slot, Dotson’s fastball changes planes well. The fastball also looks deceptively faster than it appears given its low-90s velocity. I’d wager his velocity has likely taken another step forward with any further development Dotson has managed since 2019. If Dotson can routinely operate in the low-to-mid-90s range, he could realistically become a Taylor Hearn-type multi-inning reliever prospect.

The curveball has a bit of a slurve’s appearance, in that it sweeps vertically across the strike zone almost as much as it travels horizontally through the zone. Dotson’s curve looks like a legitimate second offering, featuring some 11-5 breaking action. With the dearth of video from 2020’s instructs, these 2019 clips are the only available video on Dotson. At that time he was a two-pitch pitcher, operating mainly off his fastball and curveball. His changeup will need significant work to become an acceptable third offering. And while I would prefer the Rangers keep his development on a starter’s path while the changeup comes along, if the changeup fails to materialize, Dotson still has great potential as a two-pitch, multi-inning bullpen arm. Here’s the curveball’s action in slow-motion:

Dotson’s advanced body still has significant room to fill out. His long limbs could accommodate muscle gain, which would reinforce the velocity gains he made in his final high school years. In his first experience in professional baseball with the rookie-level Arizona League Rangers, Dotson threw 35.1 IP to the tune of a 41/13 strikeout to walk ratio. With a 2.29 ERA and a 10.44 K/9 Dotson looked the part of a potential multi-inning bullpen weapon. I was surprised to see Dotson did not receive a full season assignment to start 2021, but he could advance rather quickly through the Arizona Rookie League and debut in full season ball by year’s end.

Dylan MacLean

In 2015, MacLean appeared as a 5’ 3” 95 pound kid in the Little League World Series. He was the ace of the Northwest Team representing Portland, Oregon. In the only start I could find a stat line for, MacLean threw 5.2 IP of hitless, 12 K ball versus the Pearland, Texas team that would go on to place 3rd in the 2015 Little League World Series. As you can see, he’s always thrown the ball with a certain degree of confidence:

Further development from his 12-year-old body has left MacLean with a projectable 6’ 2” 185 pound frame that could easily accommodate further muscle gain. Any further development in his lower half would power further leaps forward in his velocity. Before his final high school season was abbreviated by the COVID-19 pandemic, we saw such gains in velocity. Going into 2020, MacLean’s near-overhand arm slot delivery produced an average velocity that tended to be in the mid-80s. By the time the draft came around, MacLean threw an easy, low-90s fastball that topped out at 93. His secondaries, a changeup and curveball, are similarly developed to his fastball and each possess 50 - 60 (average - plus) potential future values. Given time, MacLean will almost certainly exceed his selection as the 115th pick in the draft.

At present, MacLean is s a pitchability lefty with the potential to develop plus stuff to go along with his plus command on the mound. His mechanics are so easily repeated that I want to label him a young Derek Holland. There is some MORP potential in MacLean’s profile, and along with Evan Carter, he could very well be an incredible value the Rangers unearthed in the 2020 draft. Before grading his control, I’d like to get more video from the Arizona Rookie League, where MacLean will surely be building his body to get ready for a full minor league workload. I’m officially designated him as Mr. Clean, and will only refer to him as such from now on. A forthcoming collaboration between myself and LSB poster HufftheMagicDragon will focus solely on MacLean’s mechanics.

Abdiel Mendoza

I’m hoping Mendoza goes by the nickname “Diesel,” if only to keep up the alliteration between Dane, Destin, and Dylan. Upon being acquired in the Corey Gearrin trade with the Oakland A’s, Mendoza put up an excellent line in Spokane in 2018. At just 19 years old, he threw 43.2 innings to the tune of a 2.89 ERA with a 7.63 K/9, 2.89 BB/9, and 0.84 HR/9.

While he won’t bring the gasoline that you’ll see with a guy like Hans Crouse, Mendoza throws a curveball from his ³⁄₄ arm slot that is an absolute gem. It’s deserving of a 65-grade. It’s 12-6 motion is exhibited here with the pitch’s floor dropping out from under it:

It’s a magnificent pitch, one that Oakland surely used to justify signing Mendoza in 2015. At that time, he was 5’ 10” and just 130 pounds, and throwing his fastball in the mid-80s. By the time the Rangers acquired Mendoza’s services in 2018, he had put on 35 pounds, leading to a jump to consistent low-90s velocity. The curve remains his out pitch, as the fastball and his changeup flashed signs of further development.

The latest video on Mendoza’s delivery appears, to my untrained eye, to be relatively clean and repeatable. While that video’s from 2017, that fact only emphasizes the impressiveness of Mendoza’s mechanics at just 18 years old. Mendoza’s assignment to the low-A Down East Wood Ducks will be his second bite at low-A with the Rangers. In his first experience there in 2019, he threw 85.2 solid innings, and appeared to assuage concerns that his frame wouldn’t accommodate a starter’s workload. If Mendoza starts the year off well, he could soon advance to High-A Hickory. Given that Mendoza only cost the Rangers Cory Gearrin, whom was non-tendered in the 2018 - 2019 offseason, the acquisition looks like a good one. After getting both Mendoza and Acker, Texas might just want to keep up this trade pipeline with Oakland.

I don’t necessarily intend for this to represent some sort of picks to click list, but wanted to highlight these guys who deserve more attention than they have thus far received. You can do this with damn near any minor leaguer, but Mendoza’s got a knee-bending curve, MacLean’s delivery is basically flawless, Dotson’s fastball changes planes excellently, and Acker showcases at least four average pitches, with plus command. Each of these dudes has the tools to emerge from obscurity as a true prospect, and I’m excited to see how they fare in 2021. Tomorrow, we’ll be examining Dylan MacLean’s mechanics, and follow that up on Wednesday with an article on the overlooked hitters in the Rangers system. In the meantime, if you think I disregarded someone worthy of consideration as a hidden gem, feel free to throw their name into the comments!