Although they have not thrown an MLB pitch in 2023, Kenny Rosenberg threw 1,232 pitches that were tracked by the PITCHf/x system between 2021 and 2022, including pitches thrown in the MLB Regular Season and Spring Training. In 2022, they relied primarily on their Fourseam Fastball (91mph) and Change (81mph), also mixing in a Slider (81mph) and Curve (75mph).
In 2022, compared to other LHP:
His fourseam fastball has some natural sinking action and has essentially average velo. His change has surprising cut action, generates a high number of swings & misses compared to other pitchers' changeups, results in somewhat more flyballs compared to other pitchers' changeups, has slightly below average velo and has some natural sink to it. His slider has exceptional depth. His curve generates fewer whiffs/swing compared to other pitchers' curves, has a sharp downward bite, results in somewhat more flyballs compared to other pitchers' curves and has slightly below average velo.