Minor League Barometer: Risers & Fallers

Now may be the time to buy in on 18-year-old Kevin Alvarez while you can. The Cuban outfielder is currently at Low-A in the Houston Astros organization and went 12-for-23 (.571) the last week. The teenager is 6-foot-3, 185 and only beginning to scratch the surface of his potential. Arguably the system's top prospect, the sweet-swinging lefty is far more polished at the dish than his age would dictate while he offers the ability to hit to all fields, with power, and still room to fill out as he matures. With enough speed to make an impact on the basepaths, Alvarez could be a five-tool stud.

Let's take a look at some other prospects 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 2026!

UPGRADE

Ethan Salas, C, SD – Salas was a 17-year-old prodigy back in 2023, but only batted .206 with four homers at High-A the next year and then only logged 10 games the following season during an injury-riddled campaign. He's firmly back on the prospect map slashing .309/.359/.500 with seven home runs, 30 RBI and 10 steals through 44 Double-A contests. Salas finally looks to be tapping into his impressive raw power. At such a premium position and already at Double-A, he appears to be turning a corner.

Tate Southisene, SS, ATL – Southisene has been hot at Low-A by hitting over .400 alongside eight stolen bases the last two weeks. The teenage shortstop and 2025 first-rounder has produced a .299/.435/.514 line with eight homers and 35 swipes from only 47 contests. Perhaps most impressive is that Southisene displays patience at the dish, to go with emerging power and blazing speed. If his power and hit tool both remain better than initially advertised, he could rocket up the phenom charts.

Cam Cannarella, OF, MIA – Cannarella missed over a month due to a broken wrist, yet quickly rebounded after coming back at High-A going .404 with two home runs and 16 RBI through 12 outings that quickly led to a promotion to Double-A. Outside of Aiva Arquette, there's an argument the 43rd pick from last year may be the club's best remaining offensive prospect.

Blaze Jordan, 1B, STL – Jordan has been tearing the cover off of the ball at Triple-A. Dealt by the Red Sox last season, Jordan's slashing .328/.384/.551 with nine homers and 30 RBI across 49 appearances where he's only struck out 22 times. Alec Burleson is mediocre enough to keep his job at first base, though the Cardinals carry mounting outfield injuries in the outfield and the DH slot is also far from settled. If Jordan continues to rake, the Cards will have a difficult time keeping him - or Joshua Baez - down in the minors for much longer.

CHECK STATUS

Jett Williams, OF, MIL – Williams has so far endured an up-and-down campaign at Triple-A hitting .227 in April before raising that by almost 30 points through the middle of May. He's been cold the last two weeks to bring that number back down to .230. Williams does have five homers and 12 steals, yet his power numbers are down compared to a year ago. He's not afraid to take a walk, but is still striking out too much. Now 22, Williams will need to show more consistency if he wants to debut in the Majors this season.

Lonnie White, OF, PIT – Esmerlyn Valdez enjoyed a cup of coffee in the bigs during May and Tony Blanco's pop at High-A has generated serious buzz, yet it's White who's done the most to change the narrative. His future prospects looked grim after two lost High-A seasons, though he managed vast improvement for plate discipline and contact that resulted in a move up to Double-A. The toolsy White has supplied 12 home runs and 14 swipes through 48 combined matchups. While Ks remain a part of the equation, his swing decisions have been far better this year that's allowed him to regularly flash that power/speed combo. There's still plenty of room left for White to work his way back into Pittsburgh's future plans, but this is certainly a step in the right direction.

Jace Avina, OF, NYY – The outfield is crowded ahead of Avina, though the former 14th-round selection out of high school is having a career year at Double-A and is still only 22 slashing .279/.361/.589 with 14 homers, 35 RBI and five stolen bases. The improved stroke is particularly notable as he only went deep 11 times over 98 games last season between High-A and Double-A. On the flip side, Avina is striking out more often and questions remain as to whether he can hit for average at the higher levels. If his newfound power is legit, he could be dangled at the deadline as the Bronx Bombers seek bullpen help.

DOWNGRADE

Ethan Holliday, SS, COL – Holliday suffered a stress fracture in his left foot and has undergone season-ending surgery. He had just begun his first full pro campaign, where he went .262/.395/.557 with nine home runs and 32 RBI. The injury isn't expected to impact Holliday's future outlook, though obviously affects him for the rest of 2026.

Gavin Fien, OF, WAS – Fien is still only 19, but the last calendar year has been difficult. A shortstop by trade, he was shipped to the Nationals after being drafted by the Rangers in the MacKenzie Gore deal. With Eli Willits selected first alongside several other shortstops ahead of him in the system, Fien has already been shifted to the outfield. He also hurt his wrist and has yet to find his groove at the plate slashing .164/.282/.254, albeit in 17 contests at Low-A. The sample size is small and Fien should eventually have a solid professional career, though he's struggling offensively and learning a new position while already on his second organization.