Minor League Barometer: Risers & Fallers

As is customary for the Minor League Barometer, let's look at some players in the headlines before taking a deeper dive into a few profiles:

• Aidan Cremarosa tossed a no-hitter last week at Low-A in the Tampa Bay organization. The 2025 8th-round pick out of Fresno State fanned 11 batters while only walking one. This level is clearly no match for the 22-year-old who's posted a 2.38 ERA and 49:5 K:BB.
• Another player dominating there is Alirio Ferrebus with the Phillies. The 20-year-old backstop is slashing .368/.421/.613 with five home runs, 31 RBI and five steals through 28 games.
• It seems like Edwin Arroyo has been on the prospect map forever, yet he's still only 22. The switch-hitter is surging at Triple-A and pushing for a promotion to the Reds having produced a .338/.406/.573 line with seven homers, 28 RBI and five stolen bases over 38 outings.
• Wehiwa Aloy may be starting to quiet some of his doubters. Though swing and miss still remains in his profile, he's hit for average during the first 47 contests of his pro career.  Currently at High-A in the Baltimore system, the No. 30 selection from last year's Draft is batting .306 with 10 home runs.

See where future major league baseball starts slot into RotoWire's MLB Top Prospects & Rankings for 2026!

UPGRADE

Eric Hartman, OF, ATL – Atlanta may have found a diamond in the rough in the form of Hartman, a 2024 20th-rounder out of Canadian high school. He's still only 19, but is currently raking at High-A going .331/.417/.710 through 31 games. Perhaps even more intriguing is that Hartman has already recorded 12 homers and 13 steals, including two of the former on Sunday with four alongside 11 RBI the last seven days. He also swiped 48 bags last season from 89 appearances, mostly at Low-A. If this newfound power stroke is for real, the lefty-swinging Hartman will fly up the prospect charts.

Charles Davalan, OF, LAD – Davalan may be only be 5'9", yet he's done nothing but hit since being drafted 41st overall last season from the University of Arkansas where he would bat .500 over eight games at Low-A. And so far through 30 contests at High-A, he's slashing .304/.423/.527 with six home runs, 20 RBI and eight stolen bases with more walks (18) than strikeouts (17). The Dodgers' minor league outfield depth is outstanding, though Davalan represents another potential trade piece to patch up any holes before the deadline.

Joseph Dzierwa, P, BAL – A second-rounder of the O's in 2025, Dzierwa offers stellar control and an excellent change-up that allows his fastball to play up. The lack of walks is especially impressive considering the southpaw's 6'8" frame. Dzierwa has been dismantling the opposition to date at High-A with opposing batters only going .146 against. The 22-year-old Michigan State product has posted a 2.02 ERA and 44:9 K:BB in 35.2 innings and could eventually jump to Double-A.

CHECK STATUS

Ethan Holliday, SS, COL – When all is said and done, Ethan is going to be a power prospect and much more like his father than brother Jackson Holliday. After a brief 18-game stint at Double-A last year, he's returned to this level with decent success going .258/.393/.538 with six homers and 24 RBI during 26 contests.  There will be questions as to whether Holliday can hit for average at the higher levels while speed is unlikely to be part of his profile. Nevertheless, he isn't afraid to take a walk and should offer considerable power production - he just doesn't have his brother's potential five-tool repertoire.

Kyson Witherspoon, P, BOS – Witherspoon has so far struggled with command and control having walked 13 batters from 21.2 innings while opposing batters are hitting .280 against leading to a 7.06 ERA through six starts. The sample size is small and the 15th-overall pick from last year carries a pedigree as a polished collegian with a previous track record and vast repertoire of pitches, so the early issues are slightly surprising - especially at High-A.  Witherspoon still has time to right the ship, but this certainly hasn't been the start he envisioned.

DOWNGRADE

Sean Gamble, OF, KC – Gamble was viewed as a possible five-tool prospect without any weaknesses coming out of IMG Academy, though perhaps the expectations were a bit unfair as the 19-year-old hasn't looked good at Low-A having produced a .111/.206/.162 line with one homer, four steals and 40 strikeouts in only 29 outings. The 2025 No. 23 selection has looked lost and overmatched, yet has made slightly more contact the last week. It was extremely unlikely Gamble was ever going to set the minors on fire right away, but this sort of difficulty may not have been foreseen. He certainly deserves the benefit of the doubt early on, though remains a work-in-progress.

Quinn Mathews, P, STL – Flashes remain, but the dazzling 2024 for Mathews seems like a distant memory. After taking the minors by storm across four levels and amassing 202 Ks during 143.1 innings, he struggled with control last year by issuing 74 walks over 99 frames mostly at Triple-A.  Mathews' ERA was still only 3.93 and had a shot to crack the big-league rotation this spring. That didn't materialize and he's now 25 while continuing to battle control issues with 22 free passes over 26 innings and six runs against through 1.1 frames last time out. Mathews has also been prone to the long ball having allowed at least one in four straights. While it isn't time to totally give up on him, his prospect luster has certainly faded.

George Klassen, P, LAA – Klassen did get to the Majors earlier this season, where he walked 10 batters in 4.2 innings before being returned to Triple-A. The minors haven't been kind to him either as the 24-year-old southpaw has allowed 28 hits from 22 innings in the unforgiving Pacific Coast League. Klassen boasts superb stuff with inconsistent command, with the latter being what ultimately holds him back from being a frontline starter. In fact, the 24-year-old may end up in the bullpen if he can't turn it around get his act together.