At long last, the day has come. The Milwaukee Brewers are promoting their top pitching prospect, Jacob Misiorowski, to the major leagues. ESPN's MLB Insider Jeff Passan broke the news on Tuesday afternoon and noted that while Misiorowski's promotion has been decided, it will not be immediate.
The Milwaukee Brewers are calling up right-hander Jacob Misiorowski, one of the best pitching prospects in baseball, sources tell ESPN. Misiorowski, ranked 30th among all prospects by @kileymcd, has a fastball that’s been up to 103 mph this year. He’s expected to start Thursday.
— Jeff Passan (@JeffPassan) June 10, 2025
As Passan notes, Misiorowski is a flamethrower. A few weeks ago, he threw the fastest pitch by any starting pitcher at any level in the Statcast era with a 103 MPH strikeout of Luken Baker, a first base/DH prospect in the St. Louis Cardinals’ system. While his fastball is elite, it’s Misiorowski's refinement of his secondary pitches that has taken him to the next level this season. On top of his sharp slider, which he throws in the low 90s, and slower curveball that sits in the mid-80s, Miz added a changeup to his repertoire this season. Though he throws it less than five percent of the time, it gives the 23-year-old right-hander a four-pitch mix that should give him success at the big league level.
Meanwhile Misiorowski has nothing left to prove at the minor league level. After climbing through the Brewers' minor league system two seasons ago, starting the year in Low-A and ending it in Double-A, Misiorowski had the best season of his professional career last year. Splitting time between the Double-A Biloxi Shuckers and the Triple-A Nashville Sounds, Miz posted a 3.33 ERA with 127 strikeouts in just 97.1 innings pitched. He nearly cracked the big league roster at the end of the 2024 season, after converting to a reliever in Nashville, but concerns with his command prevented that move from ever happening.
Now, after two impressive months in Triple-A to start the 2025 season, with Miz posting a 2.13 ERA across 12 outings, the Brewers can't deny their top pitching prospect a spot on the active roster any longer; Jacob Misiorowski is a big leaguer.
Jacob Misiorowski to make MLB debut on Thursday against the Brewers' division rivals
The Misiorowski promotion isn't immediate, as both Passan and MLB.com's Brewers beat writer Adam McCalvy reported, but rather he is expected to join the team in two days’ time, for their matchup with the St. Louis Cardinals.
Source confirms the Brewers are calling up top pitching prospect Jacob Misiorowski, the No. 68 prospect in baseball per @MLBPipeline. Plan is to start Misiorowski on Thursday against the Cardinals at American Family Field.
— Adam McCalvy (@AdamMcCalvy) June 10, 2025
The move also gives the Brewers more time to decide on a corresponding roster move, as Misiorowski is not on the 40-man roster. The team will either have to designate someone for assignment, trade a player, or place someone on the 60-day IL ahead of Misiorowski's addition to the active roster on Thursday.
Additionally, the Brewers have yet to announce how they will construct the rest of the rotation around Misiorowski's addition. With Chad Patrick, Quinn Priester, José Quintana, Aaron Civale, and Freddy Peralta all pitching very well at the moment, the Brewers will either have to make a difficult decision or turn to a temporary six-man rotation.
Nonetheless, it's an exciting day for Brewers fans, who have long waited for Miz's arrival in the big leagues. And for Misiorowski, today's news is a testament to the dedication and hard work that he's displayed over the past few years. His willingness to tinker with his pitch mix and his ability to rein in his command are big reasons for his promotion to the major leagues.