Kelley L Cox-USA TODAY Sports
Blake Treinen has established himself as one of the premier sinker-heavy relievers in baseball throughout his career. Since his debut, he has consistently been among the top relievers in the game. From 2014 to 2022, he ranked ninth in FIP-based WAR and fourth in RA9-WAR among all relief pitchers. Additionally, he held the second-highest groundball rate among relievers with 400 or more innings pitched. Treinen’s success has been built on his effective use of sinkers and sliders.
As his career progressed, Treinen made a significant change by incorporating a sweeping slider into his repertoire. This adjustment turbo-charged his strikeout rate, leading to one of his best seasons in 2021 despite some command issues. Treinen became a pioneer in the sweeper revolution, influencing a new wave of sinker/sweeper right-handed pitchers in the league.
Unfortunately, Treinen experienced a series of injuries that sidelined him for most of 2022 and all of 2023. The road to recovery was long and arduous, involving surgeries for a capsule tear in his shoulder, rotator cuff, and labrum, along with rib fractures and a bruised lung from a line drive injury in spring training. There were doubts about whether he would return to form, but Treinen has defied expectations.
Despite a slight decrease in velocity, Treinen has maintained his effectiveness on the mound. He continues to generate high strikeout numbers while occasionally struggling with walks. One noticeable change in his performance this season is a shift in his groundball to fly ball ratio. Traditionally a groundball pitcher, Treinen has seen an increase in fly balls generated this year.
An area of focus has been Treinen’s sinker, which is producing fewer ground balls and more fly balls compared to previous seasons. His sinker’s launch angle has risen from negative values to positive angles in 2024, indicating a change in the pitch’s effectiveness. While his sinker still grades well based on pitch models, the results have been different this season.
Treinen’s sweeping slider, known for inducing popups, has been another factor in his altered pitching profile. The slider’s movement and trajectory have led to more fly balls and less ground balls, diverging from his earlier gyro slider. Despite these changes, Treinen’s cutter has become a more prominent pitch in his arsenal, particularly against left-handed batters.
These adjustments in Treinen’s pitching approach have resulted in a noticeable shift towards generating more fly balls and fewer ground balls. While it is still early in the season, the changes in his pitch outcomes raise questions about his evolving pitching style and the potential impact on similar pitchers across baseball.
