Jacob Misiorowski made a highly anticipated MLB debut on June 12, 2025, against the St. Louis Cardinals, pitching five no-hit innings in a 6-0 victory.

Facing veteran pitcher Sonny Gray, who had a strong season record, Misiorowski held the Cardinals hitless until he exited the game.

In his debut, Misiorowski became only the third pitcher in MLB history to start and pitch five or more innings without allowing a hit, joining Emmett Sheehan and Red Ames.

He showcased remarkable velocity, reaching 100 mph on multiple pitches, including a first pitch clocked at 100.5 mph, the fastest for a Brewers' starter since 2008.

Prior to his debut, the 23-year-old Misiorowski excelled in Triple-A, posting a 2.13 ERA with 80 strikeouts in 63⅓ innings.

Misiorowski's performance included a three-up, three-down second inning, and he issued his first walk after a seven-pitch battle with Nolan Gorman.

However, he exited the game due to cramping after slipping on the mound in the sixth inning, leading to his replacement by Nick Mears.

The Cardinals did not record their first hit until the seventh inning, finishing the game with only three hits.

The Brewers scored their only run in the second inning when Isaac Collins hit a two-out triple, followed by Brice Turang's infield single.

In the fifth inning, Jackson Chourio hit a two-run homer, contributing to a five-run rally that chased Sonny Gray from the game.

The Brewers' upcoming schedule features games against the Cardinals, with Freddy Peralta and José Quintana slated to start on June 13 and June 14.

Misiorowski's debut performance ranks second in Brewers' history for a debut at five hitless innings, just shy of the longest no-hit bid in an MLB debut.