Minor League Barometer: Risers & Fallers

The prospect ups-and-downs continue as the big-league season is about a quarter of the way done. Jordan Lawlar is expected to be called up this week by the Diamondbacks. The hotshot phenom has finally been healthy and is slashing a robust .336/.413/.579 with six homers, 31 RBI and 13 steals in 37 Triple-A games. Cade Horton already made his ML debut for the Cubs on Saturday as he notched the win over four innings against a difficult Mets lineup. Speaking of the Metropolitans, hurler Nolan McLean continues to sparkle as he rockets up their farm system, including seven scoreless innings during his Triple-A debut on Friday where he fanned seven and only walked one. He's not yet on the 40-man roster, but his torrid start has turned plenty of heads.

The news is not so good for Jarlin Susana, one of the top arms in the Washington organization.  Susana has been shut down from throwing for at least two weeks due to a Grade 1 UCL sprain.  Though the injury could have been worse, Susana had already been struggling with his control in 2025 prior to the discovery of the ailment.

As the weather warms up and summer fast-approaches, here are some other neophytes making headlines in this edition of the Minor League Barometer.

See where future major league baseball starts slot into RotoWire's MLB Top Prospects & Rankings for 2025!

UPGRADE

Konnor Griffin, SS/OF, PIT – Griffin just turned 19, but the ninth overall selection from 2024 has already performed as advertised at Low-A thus far having produced a .282/.341/.504 line with six home runs, 17 RBI and 13 stolen bases through 28 contests, though his plate discipline certainly needs work with 36 strikeouts and only six walks. The tools are still loud and he is basically full-grown at 6-4, 225. It's not a stretch to say Griffin could become a five-tool player when all is said and done, and his start has done nothing to dispel that notion.

Thomas White, P, MIA – White continues his journey at High-A after making 13 starts at that level last season. The 6-5, 240 southpaw continues to display standout strikeout stuff with 37 Ks across 25 frames. White has gained some velocity on his heater while his off-speed pitches have also improved. He's yet to allow a homer through six outings and opposing batters are only hitting .189 against. Other than the White Sox duo of Noah Schultz and Hagen Smith, White has a case as the best left-handed pitching prospect in baseball and should get to Double-A sometime this summer.

JR Ritchie, P, ATL – Ritchie is making his way back from Tommy John surgery. The 35th selection from the 2022 Draft went 49.2 innings a season ago during his return to the mound while posting a 2.90 ERA and 56:17 K:BB across three levels. He's overpowered the competition so far this year at High-A by registering a 1.30 ERA and 38:10 K:BB through 41.2 innings while hitters are batting .161 against. Ritchie's last start was an absolute gem as he threw a complete-game shutout (on one hit!) while punching out nine and walking one. He's since been bumped up to Double-A, so now may be a good time to buy before his stock takes off.

Lazaro Montes, OF, SEA – Montes has power to spare, though he's also hit for average since entering the minors and his plate discipline continues to be exceptional. He still has a penchant for swinging and missing with 38 strikeouts at High-A, yet he's also picked up 24 walks en route to a .401 OBP. Montes is also currently hitting .276 with seven homers and 19 RBI. He may only be 20, but Montes offers a unique combination of power and polish at the dish as one of the most coveted outfield prospects.

CHECK STATUS

Parker Messick, P, CLE – Messick could be the Rodney Dangerfield of pitching prospects since he gets no respect. Despite fanning a staggering 165 batters between High-A and Double-A in 2024, critics are quick to point out his lack of fastball velocity. Messick boasts a bevy of off-speed pitches - most notably a changeup - which plays nicely off of his low-90s heater from the left side. Now at Triple-A, the 24-year-old southpaw has a 2.76 ERA and 48:15 K:BB over 32.2 innings while the opposition is batting .202 against. The back end of the Cleveland starting rotation has been mediocre at best, so Messick could be a real option at some point later this season despite the perceived lack of upside.

Luis Pena, SS, MIL – Jesus Made looks like a star in the making for the Brewers, but Pena is another teenage phenom in the organization who skipped the Arizona Complex League and is more than holding his own at Low-A slashing .321/.398/.469 with one homer, 19 RBI and 19 steals through 20 games. His top asset is speed, though he's been more than adequate in making consistent contact with more walks (nine) than strikeouts (seven). Pena doesn't nearly carry the same power profile as Made, which is what knocks him down a couple of pegs on the overall prospect charts, yet he's already produced nine extra-base hits. If he can tap into some power potential, Milwaukee could have a superstar tandem for many years.

Jett Williams, SS, NYM – Williams couldn't stay on the field last seasons, yet he's logged nearly as many games in 2025 at Double-A slashing .283/.365/.478 with two home runs, 11 RBI and seven stolen bases across 26 outings. He also swiped 45 bags in 2023 and can rely on some power despite a short stature. There isn't an obvious spot for the Mets' top-hitting prospect to play right now, but Williams offers the speed, plate discipline and ability to handle the bat that could result in him seeing a Major League roster sometime in 2026 - assuming he can remain healthy.

DOWNGRADE

Jackson Baumeister, P, TB – Baumeister came over from the Baltimore organization in the Zach Eflin trade and dominated at High-A down the stretch with a 1.24 ERA and 44:5 K:BB through 29 innings. The fact that he pumped strikes was particularly noteworthy as he walked 43 batters in 70.2 frames at the same level prior to the deal. Double-A has been a rude awakening for the 22-year-old righty with an unsightly 8.67 ERA through seven appearances. Perhaps most concerning is that Baumeister has already issued 16 free passes. He's also been snakebitten by the long ball this season as he's conceded five. Baumeister has plenty of time to right the ship, though this is certainly not the start to 2025 he envisioned.

Owen Caissie, OF, CHC – Caissie appears to have lost some of his prospect luster and is currently on his second stint at Triple-A despite only being 22. He went .278/.375/.472 last year with 19 homers, 75 RBI and 11 stolen bases, yet continued to struggle with 156 strikeouts. Caissie returned to that level following offseason core muscle surgery and a nagging groin issue. The trade for Kyle Tucker and the emergence of Pete Crow-Armstrong have also largely blocked his path. Caissie has gone .214 through 26 games and has already fanned 41 times. With teammates Moises Ballesteros and Kevin Alcantara performing better and either the same age or younger, Caissie's stock is on the decline.