Prospects ready to climb the ladder -- one from each team

June 19th, 2024

The goal for any player entering pro ball, of course, is to reach the big leagues. It can be a long and arduous climb through a Minor League system and a select few make it.

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The 30 players below are all doing their best to move up their organization’s ladder. Their performances so far in 2024 could force the powers that be to consider moving them up one rung closer to fulfilling that ultimate dream.


Blue Jays: Adam Macko, LHP (No. 9)
With Ricky Tiedemann and Brandon Barriera both injured for much of the first half, Macko has been a much-needed pitching success story at Double-A New Hampshire. Over his last seven starts, the 23-year-old southpaw has a 3.08 ERA with 49 strikeouts and only nine walks over his last seven starts (38 innings). His four-pitch mix, including a pair of separate breaking balls in his slider and curveball, would work in Triple-A, and considering his place on the 40-man roster, he might not be far off from a second-half MLB debut either.

Orioles: Seth Johnson, RHP (No. 10)
The Orioles traded for Johnson in 2022, but they acquired him from the Rays right when he was getting Tommy John surgery, so this is really his first full healthy season with the organization. So he’s 25, but with a relatively short professional resume. He’s been in Double-A all year and has been getting sharper as the year has gone on, with a 1.31 ERA and 1.11 WHIP to go along with a 10.9 K/9 rate that points to a need to challenge him with a move to Triple-A. That could put him in line to help out the big league staff at some point this year.

Rays: Xavier Isaac, 1B (No. 3/MLB No. 45)
Isaac may have gotten off to a colder April start (.705 OPS) with High-A Bowling Green, but the left-handed slugger has caught straight fire with a .357/.440/.674 line, nine homers and nine steals in 36 games since the start of May. The 2022 first-rounder’s .579 slugging percentage on the season leads the High-A level. If there’s one bugaboo to pick, it’s that he’s struggled against lefties (.584 OPS-against), but for the most part, Isaac, who is currently day-to-day with a jammed wrist, looks like a batter in need of a new challenge.

Red Sox: Marcelo Mayer, SS (No. 1/MLB No. 11)
The Red Sox are getting inconsistent play at shortstop and the No. 4 overall pick in the 2021 Draft has proven he can handle Double-A, so it's time to at least promote Mayer to Triple-A and get him closer to Boston. He has all the tools to make an impact on both sides of the ball and he's slashing .308/.373/.487 (ranking in the top eight in the Eastern League in all three categories at age 21) with six homers and 12 steals in 59 games.

Yankees: Jared Serna, SS/2B (No. 19)
The Yankees make a habit of collecting second basemen with small frames and bigger offensive impact, including signing Serna for $10,000 out of Mexico in 2019. The 5-foot-7, 168-pounder is a solid hitter with raw power to match and he's batting .275/.375/.496 with 11 homers (one off the High-A South Atlantic League lead) and nine steals in 61 games.


Guardians: Jhonkensy Noel, OF/1B (No. 26)
Signed for $100,000 out of the Dominican Republic in 2017, Noel has prodigious bat speed and strength that give him some of the best raw power in the Minors. Hitting .295/.360/.582 and topping the Triple-A International League with 17 homers, 32 extra-base hits and 56 RBI in 60 games, he could add some more punch to the surprising Guardians -- who just demoted Kyle Manzardo and are looking for more production out of their DH.

Royals: Carter Jensen, C (No. 10)
The 20-year-old backstop is repeating High-A Quad Cities after hitting .211/.356/.363 in 116 games there last season, and through 62 contests this year, his slash line is up across the board at .287/.406/.452. His 143 wRC+ is fourth-highest among High-A catchers. Jensen maintains his high-walking ways, but he’s also cut his strikeout rate by five points from 24.1 percent to 19.4. He’s up to 780 Midwest League plate appearances, and while he’d be young for the Texas League, he has the experience and results to make a move.

Tigers: Hao-Yu Lee, 2B (No. 13)
Acquired from the Phillies last year for Michael Lorenzen, Lee moved to Double-A Erie to begin his first full season in the Detroit system, and he might not be there long. The infielder ranks among the Eastern League’s top five in slugging percentage (.513), hits (68), extra-base hits (27) and total bases (119). He’s been especially hot of late too with 10 extra-base hits and a .737 SLG over 14 games this month, strengthening his case to see Toledo soon.

Twins: Zebby Matthews, RHP (No. 19)
The Twins have a penchant for finding interesting college pitching talent in the later rounds and it’s looking like Matthews, an eighth-round pick in 2022 out of Western Carolina, is a prime example. He’s already earned a bump up from High-A to Double-A this year, but the new level doesn’t seem to be offering too much of a challenge so far, with a 1.77 ERA, 0.73 WHIP and .188 BAA in six starts with Wichita to date. Let’s get him to St. Paul and put him on the standby list to help out the big league rotation.

White Sox: Mason Adams, RHP (No. 19)
The White Sox already promoted Drew Thorpe from Double-A to Chicago and could consider doing the same with Adams, a 13th-round steal out of Jacksonville in 2022. Using a low-80s downer curveball and tremendous feel for pitching, he paces the Southern League with a 6.4 K/BB ratio while fashioning a 2.34 ERA with 70 strikeouts in 69 1/3 innings.


Angels: Adrian Placencia, 2B/SS (No. 12)
Given how aggressive the Angels are as an organization in terms of moving guys up levels, it’s a little surprising the 21-year-old Placencia is in Single-A, but pumping the breaks on him might have been just what was needed. He had been pushed to High-A and even Double-A in 2023 without much success (.664 OPS), so the Angels sent him back to Single-A Inland Empire. He has a .923 OPS there so far and has a .297/.415/.584 line over his last 30 days, so it might be time to see how he can handle a move back up to High-A Tri-City.

Astros: Jake Bloss, RHP (No. 10)
The Astros moved Bloss, a third-round pick from Georgetown last July, from High-A to Double-A in early May and it's already time for another challenge. After improving his fastball velocity (to a peak of 98 mph) and upgrading his curveball since turning pro, he's leading the Minors in opponent average (.144) while ranking fourth in WHIP (0.82) and ninth in ERA (1.74).

A’s: Grant Holman, RHP (No. 28)
After missing time with injuries over his first two years of pro ball, a move to the bullpen has paid off for Holman. He began the year as Double-A Midland’s closer and got bumped up to Triple-A Las Vegas after 17 outings. He’s made six outings there and has yet to give up a run of any kind this season. Here’s hoping he can make one more jump and settle in behind Mason Miller in the big league pen soon.

Mariners: Lazaro Montes, OF (No. 4/MLB No. 82)
Yes, he’s only 19, but it’s becoming pretty clear that the California League is no match for the young left-handed hitting outfielder. He has a .314/.419/.540 line with 13 homers and 69 RBIs over 61 games. The Mariners promoted Cole Young at age 19 from Modesto to High-A Everett in 2023 after 78 games, so there’s internal organizational precedent.

Rangers: Winston Santos, RHP (No. 15)
After struggling in High-A last year, Santos is thriving in a return to the level in 2024, challenging for the South Atlantic League pitching triple crown as he currently ranks first in wins (six) and second in ERA (2.43) and strikeouts (80 in 59 1/3 innings). A $10,000 bargain who signed out of the Dominican Republic in 2019, he owns a mid-90s fastball, a mid-80s slider and a diving mid-80s changeup, all of which are solid or better offerings.


Braves: Cade Kuehler, RHP (No. 8)
The Braves don’t shy away from moving pitchers up the ladder in a hurry, but Kuehler is still with Single-A Augusta. Some of that might be because he’s still working on refining things to give him the chance to start long-term, but he’s been throwing very well of late, with a 1.42 ERA and 0.89 WHIP over his last four starts. The improved strike-throwing is a particularly good sign and could help him punch a ticket to High-A Rome.

Marlins: Jacob Miller, RHP (No. 15)
Miller had a so-so first full pro season in Single-A last year after the Marlins drafted him in the second round out of an Ohio high school in 2022. He's looking better in High-A, ranking third in the Midwest League in ERA (3.08) with 54 strikeouts in 52 2/3 innings while working off a low-90s sinker and a plus curveball.

Mets: Brandon Sproat, RHP (No. 13)
Yes, Sproat has already been promoted from High-A to Double-A this season. But consider the following. He threw 25 1/3 innings for Brooklyn before the move and posted a 1.07 ERA, 1.11 WHIP and 32.4 percent K rate before moving up. During his time with Binghamton, he’s thrown 29 2/3 innings and posted a 1.52 ERA, 0.78 WHIP and 35.5 percent K rate. Similar sample sizes, arguably better results. The 23-year-old is more advanced than a typical Draft arm in his first full season with a fastball that can touch triple-digits, a good slider and a much-improved changeup.

Nationals: Brad Lord, RHP (Unranked on Nats Top 30)
The Nats had some exciting moves in the outfield with Dylan Crews headed to Triple-A, Daylen Lile promoted to Double-A and James Wood returning in Rochester this week. While Wood is still working his way back from a hamstring strain, we’ll keep him off here for now. Instead, Lord, who first joined Double-A Harrisburg in mid-April when injuries opened a rotation spot, has posted a 0.73 ERA and 0.90 WHIP with 62 strikeouts over his last 10 starts (62 innings) for the Senators – numbers that typically earn a push up the chain.

Phillies: Justin Crawford, OF (No. 4/MLB No. 62)
Crawford finished last year with High-A Jersey Shore and he’s picked up where he left off after a strong first full season. The speedster has 24 steals in 53 games, which surprises no one, but he’s also hitting .302/.353/.423 and he already has more homers (four) than he did in all of 2023. He's doing a better job of driving the ball without getting away from who he is as a player and his .855 OPS over his last 30 days is a sign he’s figuring things out and could be ready for a move to Reading soon.


Brewers: Eric Bitonti, 3B (No. 12)
Milwaukee chose not to get too aggressive with its 2023 third-rounder in his age-18 season and assigned him to the Arizona Complex League to open this spring. The 6-foot-4 infielder has lived up to his scouting report as a hitter with great power (four homers, .541 SLG in 26 games) but some hit-tool concerns (30.3 percent K rate) in the early going. His .255 ISO is fifth-best among ACL qualifiers. While the Brewers might want to wait a little longer to see if Bitonti makes more contact, the prospect is certainly trending toward seeing Single-A Carolina this summer.

Cardinals: Quinn Mathews, LHP (No. 20)
Like Sproat above, fellow 2023 pick Mathews already moved up one level this season. Unlike Sproat, the former Stanford lefty hasn’t seen Double-A yet. It’s about time he should. Mathews is riding a streak of four straight quality starts for High-A Peoria and owns a 2.87 ERA and 0.74 WHIP with 51 strikeouts and only six walks in 37 2/3 innings since debuting in the Midwest League on May 10. His improved velocity, plus changeup and improved slider would all play in the Texas League.

Cubs: Owen Caissie, OF (No. 2/MLB No. 35)
The Cubs are struggling to score runs, so why not see if one of the best power prospects in the game can bolster their offense? Acquired from the Padres in the 2020 Yu Darvish trade, he has continually thrived against older competition and is slashing .284/.407/.464 with eight homers in 62 Triple-A games at age 21.

Pirates: Charles McAdoo, OF/3B (No. 30)
The Pirates may have found a Day 3 bargain in McAdoo, whom they took in Round 13 of the 2023 Draft. He made a very strong first impression with a .922 OPS with Single-A Bradenton last summer and he’s raised the bar even more this year, hitting .333/.413/.557 over 59 games with High-A Greensboro. The underlying data has also been really good while also showing some defensive flexibility by playing third and some second.

Reds: Hector Rodriguez, OF (No. 13)
Acquired at the 2022 Trade Deadline from the Mets, Rodriguez has hit pretty much wherever he’s been, including being the Dominican Winter League’s Rookie of the Year this past offseason (.309/.344/.487). The power hasn’t shown up much yet, but he’s continued to rake with High-A Dayton and has been hot of late, hitting .330 over his last 100 at-bats with a miniscule strikeout rate.


D-backs: Adrian Del Castillo, C (No. 27)
With Triple-A Reno for a second straight season, Del Castillo hasn’t cooled off at any point in 2024 and enters Wednesday with a .335/.399/.630 line and 14 homers through 64 games. While some of that impressive slugging can be chalked up to Reno’s hitting environs, the backstop has the data to back it up with exit velocities and in-zone contact rates above the Triple-A average. If anything happens to Gabriel Moreno or Tucker Barnhart in the bigs, Del Castillo should be Arizona’s first call.

Dodgers: Justin Wrobleski, LHP (No. 14)
An 11th-round pick out of Oklahoma State in 2021 after having Tommy John surgery two months before the Draft, Wrobleski features a 93-96 mph fastball with run and carry, impressive feel for a solid mid-80s slider and a reliable changeup. He's carving up Double-A hitters with a 3.06 ERA (fifth in the Texas League) and 4.8 K/BB ratio (second).

Giants: Jonah Cox, OF (No. 27)
The son of former big leaguer Darron Cox, Jonah put together a 47-game hitting streak (third-longest in NCAA Division I history) last spring at Oral Roberts before going in the sixth round of the draft to the Athletics and later moving to the Giants in a trade for Ross Stripling. The speedster is doing a better job of making contact in his first full pro season than he did in his debut, batting .308/.423/.389 with 38 steals (tops in the Single-A California League, second in the Minors) in 53 games.

Padres: Isaiah Lowe, RHP (No. 19)
Shoulder problems have dogged Lowe since San Diego took him in the 11th round in 2022, but he’s been healthy and productive for Single-A Lake Elsinore this season. Lowe owns a 2.86 ERA and has struck out 58 batters (most in the San Diego system) over 44 innings. He’s also pushing his workload with three straight starts of six innings or more, and his 85 pitches on June 1 marked a career high – another key sign in his push for High-A Fort Wayne.

Rockies: Sean Sullivan, LHP (No. 13)
Our Rockies entry on our hottest pitching prospect for each team at the end of May, Sullivan’s advanced feel for pitching clearly needs a new challenge. He’s second in WHIP, tied for second in strikeouts and sixth in ERA in the High-A Northwest League with a ridiculous 72/5 K/BB ratio. He’s been even better of late (30/2 K/BB ratio, .168 BAA, 1.52 ERA over his last four starts).