May 28-June 3, 2024

Justyn-Henry Malloy (OF/DH, DET)

The players covered in this column are only those who still have rookie status as determined by MLB, and who have not already been written up earlier in 2024. Find previous Call-up profiles on the Content tab of the player's PlayerLink page. 

Contributing writers: Jeremy Deloney, Chris Blessing, Nick Richards, Matthew St-Germain, and Tanner Smith


June 3, 2024

Justyn-Henry Malloy (OF/DH, DET)
Justyn-Henry Malloy, acquired by the Tigers from the Braves in the 2022 offseason as the main return for reliever Joe Jiménez, was promoted as a long awaited callup for many Tigers fans after two years of producing in AAA. Malloy has posted a .272/.417/.474 slash line in AAA over 3 seasons (primarily 2023-2024), including a .255/.412/.477 line so far in 2024. Malloy’s calling card is his plate discipline, as he is among the most patient hitters in all the minor leagues, reflected in his 20% BB% so far in 2024 and his 18% BB% the previous year. The RHH Malloy combines this patience with plus raw power and the ability to consistently pull the ball to allow that allows that power to play, although he often struggles with the ball away and is often more passive than patient. Malloy was drafted as a third baseman, but years of struggles there convinced the Tigers should be shifted to the outfield, where is decidedly below-average due to poor foot speed and lack of experience. He is likely a long-term DH. Malloy may struggle to maintain his minor league walk rate if MLB pitchers attack him in the zone in spots where he struggles, so it will be up to Malloy to punish mistakes often enough to allow his plate discipline to continue to carry his profile. There is a path for Malloy to be an everyday player for now between OF and DH and long-term, but there is a lot of pressure on his bat given his complete lack of defensive value.
STATSMalloy Baseball-Reference page
CURRENT ROLE: Starting Outfielder
POTENTIAL: Starting Outfielder

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Daniel Schneemann (INF/OF, CLE)
The Guardians called up Daniel Schneemann, a former 33rd round pick from 2018, to serve as a utility infielder with the demotion of outfielder Johnathan Rodriguez to AAA. The left-handed hitting 27-year-old has earned his promotion by leveling up his offense. He hit .217/.297/.314 across two AA seasons in 2021-2022, but in AAA he has slashed .272/.379/.467, with the best of his production coming in 2024 (.294/.428/.556). Schneeman has a quiet setup, with relatively high hands and a open stance that starts on his front toe that leads to a small leg lift and minimal hand load to a classic lefty swing with significant loft. He is a patient hitter who hits the ball hard consistently but is prone to swing and miss. Schneemann is likely a utility man, capable of playing all around the infield and outfield, but he is capable of providing slightly below MLB average offense in that role, tilted more toward power/patience than batting average. 
STATS: Schneemann Baseball-Reference page
POTENTIAL: Utility Man 

Jamie Westbrook (INF/OF, BOS)
Jamie Westbrook, a 29-year-old journeyman, gets the call for his potential MLB debut after a wave of Red Sox infield injuries, including most recently Vaughn Grissom and Romy González, left the Red Sox very short-handed up the middle. Westbrook has posted solid performances in AAA the last two years, with a .294/.400/496 line in 1117 games in the Yankees system in 2023 and a .267/.364/.436 line so far in 2024 in AAA for the Red Sox. His plate discipline numbers particularly have stood out, with well above-average BB rates in the 12-14% range and good K rates in the 16-19% range. Westbrook also possesses excellent defensive versatility, playing almost every infield or outfield position in the last two years with the exceptions of SS, CF, and C. In a normal MLB infield situation Westbrook would likely not see very much PT but the Red Sox likely have some AB available with their current infield situation and the 5’7’’ utility man may provide a few decent PAs while he is up. 
STATS: Westbrook Baseball-Reference page
POTENTIAL: Utility Man 


June 2, 2024

No Callups today.


June 1, 2024

Justin Sterner (RHP, TAM)
The Rays recalled the 27-year-old after they optioned LHP Tyler Alexander to Triple-A. Sterner was originally signed as a non-drafted free agent by the Marlins in 2020 and they later dealt him to Tampa Bay in 2021. He has spent his entire career in the bullpen (sans one start) and has found success with his unusual delivery and release. Sterner bounced between Double-A and Triple-A in 2022 and 2023 and has spent all of 2024 in Triple-A where he is enjoying his best pro season to date. He’s allowed a 3.60 ERA and .200 oppBA while maintaining his strikeout rate and lowering his walk rate. The deception in his delivery allows his 89-93 mph to be tougher to square up and has the movement to pitch up in the zone effectively at times. His most used pitch is a very good slider that features a lot of horizontal break. Sterner has allowed a lot of flyballs and HR in his career, though he generally commands his pitches well. He will likely be used as a middle reliever only and could pitch multiple innings if needed. For his career, he has a 4.14 ERA, 3.6 BB/9 and 12.0 K/9. 
STATS: Sterner Baseball-Reference page
CURRENT ROLE: Middle reliever
POTENTIAL ROLE: Middle reliever


May 31, 2024

No Callups Today.


May 30, 2024

Keider Montero (RHP, DET)
Pronounced “kay dare” rhymes with “day care”, Montero was a lesser known commodity a few years back, in a thin-at-the-time Detroit system that’s perpetually been unable to develop IFA starting pitching. 2023 would see him break out a bit, maintaining his velocity for multiple innings due to filling out—Montero’s listed 145-pound weight is comically outdated as he’s easily 60 pounds heavier since his 2016 signing—moving through three levels and ending the year with a 42.0 IP run in Triple-A putting up serviceable numbers with improved swing-and-miss. Montero tightened his spotty command on his four-pitch mix, but significant questions remain. The 23-year-old’s repertoire is led by his four-seam fastball (55% usage), working mid-90s with around 16” IVB and -5.02 VAA, giving it enough ride up in the zone for a plus projection grade coming into the year, though it’s flashing down to average as he leaking it into the zone too often in ’24. His mid-80s slider is his preferred secondary and is operating more as an above-average pitch this year, versus his curveball which despite huge 2800+ rpm spin still hovers around average. The real measure of the profile’s future role and projection hinges on Montero’s fourth pitch, the changeup, which is now rarely used (5%) and garnering fringe-average modeling grades. He’ll have to greatly up its efficacy and usage if he wants to transition as a starter as his platoon splits vs LHB are stark—.161/.278/.307 vs RHB, .340/.436/.547 vs LHB. There’s the potential for above-average command, but Montero’s also struggling here as well (12.7% BB), as his pitches tend to leak into the heart of the zone too often. As he currently is lacking both solid command and the ability to get LHB out, he’s tracking less towards back-end starter and more a bulk/long relief role. Montero is still plenty young at 23 with a frame and track record to eat significant innings in the rotation. And there’s still time to figure it out in an improving developmental organization. He's currently up in a spot start capacity and possibly on the Toledo shuttle, but all signs point to big league struggles in his first taste and more time in Triple-A fine tuning.
STATSMontero Baseball-Reference page
CURRENT ROLE: Starting Pitcher
POTENTIAL: #5 Starter/Bulk Reliever


May 29, 2024

Spencer Schwellenbach (RHP, ATL)
It’s not often that a pitcher gets the call with all of 13.0 IP above high Single-A, but such is the case for the 23-year-old Schwellenbach who's gotten even better post Double-A promotion. 6’1” and 200 pounds, the Saginaw, MI, native was a two-way (SS) player for Nebraska taken in the 2nd round in 2021 and immediately underwent Tommy John surgery, missing all of ‘21 and ‘22. Schwellenbach came back for ‘23 without much rust at all and now in ‘24 has come on strong over the last month, precipitating the rather cavernous jump to the majors. Armed with a solid four-pitch mix with the potential for plus control, his relatively quick developmental runway is especially promising considering he’s newly focusing solely on pitching. The fastball sits 95, touches 98, and has found a bit more ride this year but probably hovers just south of plus. More known for two above-average breaking balls in his cutter-like slider and slurvy curveball, it’s the development of his previously fourth offering in his change-up which has amplified Schwellenbach’s trajectory. The pitch now flashes plus with significant fade and improved command, giving him four above-average offerings on an athletic, repeatable delivery. It's a small sample, but his pitch metrics in Double-A are outstanding: 69.6% zone contact%, 38% o-swing%, 37.6% CSW%, 37.2% whiff rate, 18.5% SwK%, 56% GB%, 12% FB%, 38.6% K%, 2.3% BB%, and 0.191 wOBACON. Again, this is 13 IP, so we need significantly more data before changing Schwellenbach’s projection beyond a back-to-mid rotation starter, and cannot forget the significant injury history to his elbow and shoulder. Further, both high Single-A Rome and Double-A Mississippi are some of the best places to pitch in the minors and before his last start on the road in Chattanooga, he did have a significant home/road split. Schwellenbach only went 65.0 IP last year so one would imagine his ‘24 IP ceiling hovers somewhere around 90-110 IP, a rate he’s nearly halfway to in May, so expect an eventual shutdown regardless of his success. Despite these caveats the arrow is decidedly up. 
STATSSchwellenbach Baseball-Reference page
OTHER COVERAGENo. 5 on ATL Org ReportEyes Have It (May 2024)
CURRENT ROLE: Starting Pitcher
POTENTIAL: #3 Starter

Trenton Brooks (1B, SF)
Entering the it’s-now-or-never phase of his professional career, Brooks is seeing his skills coalesce alongside a brief window of opportunity brought upon by both injury and lack of organizational depth at 1B. 5’10” and 195 pounds, Brooks is not an ideal 1B nor projects as a starter there, with an offensive skill set (hit well over power) more suited for utility without the defensive acumen to project anywhere beyond 1B and even there his work around the bag remains a work in progress. Offensively, his contact skills are above-average—86% zone contact, 18% chase rate, 8.3% SwK, 19.7% whiff rate, 23% CSW—but the impact is marginal at best—87.3 mph avgEV, 100.6 mph 90th%EV, 3.4% barrel rate, 37% hard hit rate, 26% FB%. Still, Brooks’ ability to handle both fastballs and breaking balls from the left side gives him some strong-side platoon possibilities with LaMonte Wade Jr. (1B, SF) out for at least a month and Wilmer Flores (1B, SF) not particularly turning back the clock with a .214/.284/.290 slash in backup reps. So if Brooks hits there’s a good chance he sticks up, otherwise David Villar (3B, SF) likely next up for 1B AB against RHP. Absent a significant change of fortunes on bat-on-ball impact, this at 29-years-old is a backup 1B profile at best, maybe a brief 2nd-division starter for a team like Oakland, whom he was just traded away from for Sean Newcomb (LHP, OAK) last August. 
STATSBrooks Baseball-Reference page

Grant Koch (C, PIT)
The Allegheny Catcher Graveyard claimed another soul with Joey Bart (C, PIT) joining Endy Rodríguez (C, PIT) and Jason Delay (C, PIT) on the IL, forcing 25-K-in-54-AB Koch into emergency back-up duty, a role well above his projection of minor league catching depth. 5’10” and 195 pounds, offensively everything here is bottom-of-the-barrel: 43% whiff%, 81.4 mph avgEV, 65.6% zone contact, 36% chase rate, 0% barrel rate, 20% SwK, 43% GB%, 22% waste swing%, .171 xwOBA. Defensively this isn’t a skill set that projects even in a reserve role as Koch’s high minors CS% hovers around 15%. There otherwise aren’t many unforced errors here so he works as an emergency backstop to Yasmani Grandal (C, PIT) so Pittsburgh should be looking at Henry Davis’ (C, PIT) May Triple-A numbers and consider an encore performance for their young catching prospect absent finding an emergency free agent catcher to bridge the gap.
STATSKoch Baseball-Reference page
POTENTIAL: Minor League Backup C


May 28, 2024

J.P. Martinez (OF, ATL)
Replacing OF Ronald Acuña Jr. is a nearly impossible task. Martinez has been recalled from Triple-A and he won’t be expected to match Acuna’s production. The 28-year-old, however, has some useful skills that could lead to some playing time in all outfield positions and could provide some SB output if given the opportunity to play. The left-handed hitter was signed out of Cuba for $2.8 million by the Rangers and it took him 5 years to get to the majors, when he earned 40 AB in 2023. He hit .225/.250/.325 before the Braves acquired him via trade in January 2024. Martinez offers average raw power with above average speed. He routinely steals 20+ bases per season, including a high of 41 in 2023. Despite a long swing and a demonstrated inability to recognize or hit breaking pitches, he gets on base via walks and can use his speed to his advantage. While his contact rate has improved, it still isn’t up to snuff to warrant a full-time role. He has also gotten better against left-handed pitchers. Martinez is a sound defender in CF with an average arm and has seen action in both corners as well. For his minor league career, he has a line of .258/.361/.437 with a high of 15 HR in 2022. 
STATS: Martinez Baseball-Reference page

Alex Speas (RHP, HOU)
Given the journeys that the 26-year-old has encountered in 2024, the hope is he has a sturdy set of luggage. Speas has been summoned to the majors, his first jump to the big leagues since 3 games with the Rangers in 2023. The 6’3” 205 pounder was selected in the 2nd round in the 2016 draft, but a number of injuries (Tommy John surgery, broken leg) and a one-year retirement due to mental health concerns all led to significant development time lost. He set a personal best in innings pitched in 2023 when he threw 56.2 innings. The White Sox claimed him off waivers in October 2023 and then later lost him to the Athletics in April of this year. Then, he latched on with Houston. He’s pitched for three Triple-A teams in 2024 and has posted a 10.91 ERA and .348 oppBA in 15 games out of the bullpen. On pure velocity and a sometimes unhittable fastball, Speas has a premium pitch to dominate. Adding to that is a hard cutter that hitters bury into the ground. The big ‘however’, however, is a complete inability to command any of his offerings. He routinely puts hitters on base with walks and he racks up high pitch counts, leading to quick outings, even out of the bullpen. Speas has a fastball that touches 100 mph and the cutter comes in in the low 90s. He was dynamite in the first half of 2023 while in Double-A, but resorted to his personal mean in Triple-A upon a promotion. For his career, he has a 4.86 ERA, 7.3 BB/9 and 13.8 K/9. 
STATS: Speas Baseball-Reference page
CURRENT ROLE: Middle reliever
POTENTIAL ROLE: Setup reliever

Ryan Bliss (INF, SEA)
The Seattle Mariners recalled the 24-year-old after placing INF Jorge Polanco on the injured list. Bliss was initially selected by the Diamondbacks in the 2nd round of the 2021 draft. He had a career year in 2023 between Double-A and Triple-A (23 HR, 55 SB) before he was dealt to Seattle at the deadline. Standing only 5’7”, Bliss has built quite a nice career for himself and can do everything relatively well on the diamond. Though he isn’t blessed with above average pop, he combines sneaky strength with exceptional bat speed. If given the opportunity, the right-handed hitter could get to 15+ HR at the big league level. He stands out with his plus speed. He is also a smart, instinctual baserunner who can take the extra base and load up on SB. Because of his aggressive nature, he can expand the strike zone and make questionable swing decisions. He has struck out at least 118 times in each of the last two seasons and is well on his way to another 100+ K campaign in 2024. Thus far in Triple-A, he’s batting .247/.382/.445 with 7 HR and 28 SB. Bliss is a very good defender at both 2B and SS, though may be better at the former due to fringy arm strength. He brings reliable hands and quick feet to the infield and makes the routine plays. The future looks bright for Bliss and he will be given an opportunity to contribute to the big league club. For his career, the right-handed hitter has batted .262/.347/.445. 
STATS: Bliss Baseball-Reference page
OTHER COVERAGE: No. 5 on SEA Org Report
CURRENT ROLE: Utility player


Scale of (1-10) representing a player’s upside potential
10 - Hall of Fame-type player
9 - Elite player
8 - Solid regular
7 - Average regular
6 - Platoon player
5 - Major League reserve player
4 - Top minor league player
3 - Average minor league player
2 - Minor league reserve player
1 - Minor league roster filler

Scale of (A-E) representing the player’s realistic chances of achieving their potential
A - 90% probability of reaching potential
B - 70% probability of reaching potential
C - 50% probability of reaching potential
D - 30% probability of reaching potential
E - 10% probability of reaching potential

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