Looking at the most aggressive recent prospect assignments

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The new-look Nationals aren’t afraid to be aggressive.

They made that clear early this season when, after a full Spring Training of singing his praises, they promoted infielder Ronny Cruz to High-A Wilmington after only 14 Single-A games, the only 14 he’d ever played at the lowest full-season level. Washington will continue that tradition this week when it will move 2025 first overall pick Eli Willits to Wilmington and fellow Top 100 prospect Devin Fitz-Gerald to Double-A Harrisburg. Willits will become the first 18-year-old to appear at the High-A level in 2026, and he isn’t even the first high-schooler from the Nationals’ 2025 Draft class to reach Wilmington since Miguel Sime Jr. got there first last week. Fitz-Gerald will be one of only eight position players in their age-20 seasons or younger to get regular time at Double-A this season; six of the others (Jesús Made, Leo De Vries, Franklin Arias, Rainiel Rodriguez, Ethan Salas, Arjun Nimmala) rank among the top 55 overall prospects in baseball.

The old adage remains true here -- if you want to know how an organization feels about its prospects, watch how they move them through the system. It can be just as revealing as anything the org says publicly. In most cases, clubs will praise their top-performing prospects (why wouldn’t they?), but if they back that up with a new challenge in the form of a promotion, you know they expect big things. Iron sharpens iron. If they say good things publicly but continue to hold a player back, that speaks volumes too about how much they believe the player still has to work on at their current level.

In light of this week’s moves, let’s explore some of the other aggressive promotions this season and what they’ve meant for the players involved:

Rainiel Rodriguez, C, Cardinals (No. 2/MLB No. 22): Rodriguez played only four games with High-A Peoria during a late-season cameo as an 18-year-old in 2025, so it was no shock to see him return to the Midwest League as a teenager again this spring. He got off to a solid start with a .311/.430/.519 line with four homers in 28 games before St. Louis decided that was enough and pushed him to Double-A Springfield on May 12. Since then, he’s become only the fourth age-19 catcher to get more than 50 plate appearances in Double-A since 2006, joining Jesus Montero (2009), Keibert Ruiz (2018) and Samuel Basallo (2024) on that list.

That’s important context for this next bit because it hasn’t been easy swimming for Rodriguez in the deep end of the Texas League so far. The right-handed slugger has hit just .178/.295/.233 with one homer, a 48 wRC+ and a 29.5 percent strikeout rate in his first 20 games with Springfield. That’s still very much small-sample territory, so no one should be concerned here. Even in the down offensive time, Rodriguez’s move allows him to work with more experienced pitchers at Double-A and also big-name arms with impressive stuff like Liam Doyle and Jurrangelo Cijntje. That’s a key piece of his defensive development too. Allowing Rodriguez to mash in the Midwest League would have looked great on his stats page, but as folks in Cardinals player development say often, they’re trying to make him a great Major League catcher, not just a great High-A one.

Josiah Hartshorn, OF, Cubs (No. 7): Willits won’t be the first high-school position player from the 2025 Draft to see High-A. That honor belonged to Hartshorn, a sixth-round pick last year out of the California prep ranks. Hartshorn previously appeared in this newsletter in our early version of the All-Breakout Team on May 19, and he was promoted from Single-A Myrtle Beach to High-A South Bend exactly one week later. It was pretty clear why the switch-hitter needed to move. Hartshorn showed impressive discipline in the Carolina League, walking 34 times compared to 27 strikeouts in 39 games, and his 1.3 BB/K ratio and 19.2 percent BB rate still rank sixth and seventh respectively among 201 Single-A qualifiers. He also only swung at 38.6 percent of his pitches seen -- a number that would put him in the bottom 10 in the Majors. In other words, he needed to start facing pitchers who could throw the ball in the zone more.

Since the move, his swing rate has crept up a bit to 42.2 percent, and he’s traded some overall contact in the process. But generally, his production hasn’t skipped a beat, and he’s actually hitting for more power at the higher level with a .395/.453/.744 line and four homers through his first 12 games with South Bend. He went deep five times in more than triple the gametime (39) with Myrtle Beach. Hartshorn signed for a sixth-round record $2 million, so clearly the Cubs saw him as closer to a second-round talent, and he’s looking like more of an all-around hitter with each passing week.

Seth Hernandez, RHP, Pirates (No. 1/MLB No. 3): You won’t catch many in the industry saying Hernandez’s move from Single-A to High-A in mid-May was aggressive, per se, simply because he was just so dominant with Bradenton (0.96 ERA, 50 strikeouts, seven walks in 28 innings). His upper-90s fastball and full complement of offspeed pitches (slider, curveball, changeup) were too much for Florida State League batters, and they chased 40 percent of Hernandez’s pitches outside of the zone (per Synergy) in search of any and all possible contact.

Getting that much chase is really promising, but it can say more about the hitters at such a low level than it does about the pitcher. Plus, the Pirates likely wanted Hernandez to learn the lesson that he can’t expect batters to be so undisciplined as he climbs toward Pittsburgh. Indeed, Synergy has opponents chasing at 30 percent through Hernandez’s first four status with High-A Greensboro, and his walk rate has climbed from 6.7 percent at Single-A to 18.1 one step higher. The overall swing-and-miss is still very much there, so learning to get his impressive stuff more in zone will be an important lesson in Hernandez’s steps toward becoming another possible true ace in Pittsburgh.

Jonah Cox, OF, Giants (No. 24): Playing in his fourth Minor League season, Cox certainly looked ready for Triple-A this spring. His .400 average through 44 games at Double-A Richmond is still the best mark among Minor League full-season qualifiers, as is his 186 wRC+. Instead, the Giants decided to skip over the Pacific Coast League entirely and called up the 24-year-old outfielder to the Majors on May 31.

While the average is certainly the shiniest thing on Cox’s resume this season, it’s his speed that might be of most use to the Giants right away. Cox swiped 27 bags in those 44 games with Richmond and stole 58 bags in back-to-back seasons in ‘24 and ‘25, numbers that back up his plus-plus speed evaluation. Those same wheels help him pick up hits in bunches and fuels his high BABIPs. Entering Tuesday, the Giants rank last in the Majors with 18 steals as a team, and Cox is already responsible for two of the club’s three fastest Sprint Speeds. Manager Tony Vitello said San Francisco was hopeful Cox could “inject a little life into the locker room,” and the rookie has the momentum to do that, even if he had to skip Sacramento first.