Milwaukee Brewers pitcher Jacob Misiorowski entered the record books Friday night with a blistering 104.5 mph fastball against the Philadelphia Phillies, marking the fastest pitch ever recorded by a starting pitcher in Major League Baseball history. The right-hander’s cannon arm caught the attention of everyone at American Family Field during the top of the first inning, when he faced off against Phillies leadoff hitter Kyle Schwarber. The scoreboard initially flashed 105 mph before the official reading settled at 104.5 mph, a number that immediately sparked discussions across baseball.
The historic pitch came on a 2-2 count to Schwarber, barely catching the lower outside corner of the strike zone. Schwarber made contact on a check swing, with catcher William Contreras securing the ball. While the veteran Phillies hitter began arguing the call with the umpire, fans and commentators were fixated on something far more remarkable displayed on the stadium’s video board.
Five consecutive pitches above 103 mph stun baseball world
What made Misiorowski’s performance even more extraordinary was the sustained velocity throughout the entire at-bat. All five pitches thrown to Schwarber registered north of 103 mph on the radar gun, demonstrating remarkable consistency at an elite speed. The third pitch of the confrontation, called a strike by the home plate umpire, also reached the 104 mph mark. This relentless barrage of triple-digit heat left little room for the experienced Phillies slugger to adjust.
For Schwarber, the at-bat represented a nearly impossible challenge. Facing a young pitcher capable of maintaining such extreme velocity pitch after pitch fundamentally changes the dynamics of the plate appearance. The margin for error becomes razor-thin when every offering arrives at speeds exceeding what most hitters see throughout an entire season. Baseball analysts noted that sustained velocity at this level is unprecedented for a starting pitcher expected to work multiple innings.
Aroldis Chapman still holds overall MLB velocity record
Despite Misiorowski’s achievement as a starter, the overall MLB record for hardest pitch ever thrown remains with veteran reliever Aroldis Chapman. The Boston Red Sox pitcher established the benchmark back in 2010 during his rookie season with the Cincinnati Reds, unleashing a staggering 105.8 mph fastball that has stood atop the record books for over a decade. That single pitch represented the absolute peak of human throwing capability measured in professional baseball.
Chapman also claims the second-fastest pitch in MLB history, a 105.7 mph heater delivered in 2016 while wearing a Chicago Cubs uniform. The left-hander’s dominance at the top of the velocity charts underscores the rarity of what Misiorowski accomplished as a starting pitcher. Relievers typically throw harder than starters because they only pitch one inning at a time, allowing maximum effort on every pitch without concern for pacing themselves through multiple frames.
- Fastest pitch by a starter: Jacob Misiorowski at 104.5 mph (2024)
- Fastest pitch overall: Aroldis Chapman at 105.8 mph (2010)
- Second-fastest pitch overall: Aroldis Chapman at 105.7 mph (2016)
- Misiorowski’s five pitches to Schwarber all exceeded 103 mph
Distinction between starters and relievers in velocity context
The separation between starter and reliever velocity records highlights fundamental differences in how pitchers are used in modern baseball. Starting pitchers must conserve energy to work through five, six, or seven innings, making sustained triple-digit velocity extraordinarily difficult to maintain. Relief pitchers, particularly closers, can empty the tank for a single inning, allowing them to reach maximum velocity without worrying about fatigue over extended outings.
Misiorowski’s ability to throw multiple pitches above 104 mph while serving as a starter challenges conventional wisdom about pitcher workload management. Teams typically monitor starter velocity carefully, watching for signs of fatigue that might increase injury risk. The Brewers’ willingness to allow their young pitcher to throw at maximum effort early in games suggests confidence in his physical conditioning and biomechanics. Modern training methods and enhanced understanding of pitcher health have enabled some starters to push velocity boundaries previously considered exclusive to relief specialists.
Young pitcher joins elite velocity company in MLB history
Breaking into the conversation alongside Chapman represents a significant milestone for Misiorowski’s young career. The right-hander joins an extremely select group of pitchers capable of reaching the 104 mph threshold, a club with membership in the single digits throughout baseball history. While several pitchers have touched 102 or 103 mph, sustaining velocities above that mark requires exceptional arm strength, mechanics, and physical gifts that few possess.
The performance against the Phillies demonstrated that Misiorowski’s velocity is not merely a single-pitch outlier but a repeatable weapon he can deploy consistently. Friday’s outing provided evidence that the Brewers possess a potentially dominant force in their starting rotation, assuming the young pitcher can harness his extraordinary arm strength with command and durability. Teams throughout the league will now prepare for Milwaukee knowing they must face one of the hardest-throwing starters in baseball history whenever Misiorowski takes the mound.
