The Brewers’ minor league system remains strong, even after several top prospects have moved on to the majors in recent years. The addition of three new names to the top 20 prospect list highlights the organization’s continued depth.
No. 13 – 2B Josh Adamczewski
Selected in the 15th round of the 2023 draft, Adamczewski turned down a commitment to Ball State to sign with Milwaukee. Although he missed part of 2024 due to injury, he made a strong impression when healthy, posting an impressive 156 wRC+ between the Arizona Complex League and Low-A Carolina. He’s started even better in 2025.
Adamczewski stands out primarily for his hitting skills. His contact ability is promising, and he’s shown he can drive the ball to all parts of the field. Analyst Chris Clegg noted recent mechanical tweaks—adjusting hand placement and stance—to improve his timing and reduce ground balls. So far, those adjustments are paying off.
Though not known for overwhelming power, Adamczewski leverages launch angles and pull-side pop to generate unexpected slugging potential. He’s already hit balls up to 108 MPH and consistently produces extra-base hits.
Defensively, he’s a solid second baseman with good instincts, though limited arm strength likely keeps him off other infield spots. His hustle has led to a few key plays this season, such as backing up first base and turning potential errors into outs.
No. 15 – RHP Bishop Letson
Letson, picked in the 11th round of the 2023 draft and lured away from Purdue, had a solid debut season in 2024 with a 3.13 ERA at age 19. He’s showing even greater progress in 2025.
Armed with a four-pitch mix, Letson throws both four-seam and two-seam fastballs at 92–95 MPH, with the four-seamer topping out at 98. Thanks to his exceptional 7.5 feet of extension, his fastball plays even faster. The two-seamer shows significant arm-side run, while the four-seamer excels up in the zone.
He also has a sharp, swing-and-miss slider in the low 80s and a changeup in the mid-80s with good fade. While the changeup still needs more consistency, it flashes the potential to be a quality pitch.
Letson’s biggest improvement in 2025 has been his control—cutting his walk rate in half from the previous season. If he sustains these gains and handles a full workload, he projects as a legitimate big-league starter.
No. 19 – 1B Ernesto Martinez Jr.
Martinez, who signed back in 2017, is older than most prospects at 25 but continues to rise. After a strong 2024 at Double-A Biloxi, especially in the second half, he returned to the Brewers on a minor league deal. Despite being sidelined with an injury, he began the 2025 season well at Triple-A Nashville.
At 6’6” and 250 pounds, Martinez is a remarkable athlete. He plays strong defense at first base—highlighted by his flexibility and surprising speed, even spending occasional time in center field. He stole 20 bases in 25 tries last year, rare for someone his size.
What’s fueled his rise, though, is his offensive production. His 145 wRC+ in Double-A was impressive, but it’s his underlying metrics that stand out. Martinez hits the ball extremely hard, with a 90th percentile exit velocity of 111.5 MPH—on par with MLB stars. Surprisingly, he combines that power with a relatively low whiff rate and good plate discipline.
The only slight concern is his ground ball tendency, which may be limiting his home run output. Still, the overall offensive profile is very promising.
Turning 26 in June, Martinez seems ready for the big leagues. While a call-up this year may depend on injuries, he appears to be the frontrunner for Milwaukee’s 2026 starting first base job.
