Non-MLB
Although they have not thrown an MLB pitch in 2023, Duane Underwood Jr. threw 2,954 pitches that were tracked by the PITCHf/x system between 2018 and 2022, including pitches thrown in the MLB Regular Season and Spring Training. In 2022, they relied primarily on their Cutter (93mph), Sinker (95mph) and Change (90mph), also mixing in a Curve (83mph) and Fourseam Fastball (96mph). He also rarely threw a Slider (85mph).
In 2022, compared to other RHP:
His cutter is blazing fast, has little cutting action and has some natural sink. His sinker generates more whiffs/swing compared to other pitchers' sinkers, results in many more groundballs compared to other pitchers' sinkers and has well above average velo. His change is thrown extremely hard, generates an extremely high number of swings & misses compared to other pitchers' changeups, has slight armside fade and has some natural sink to it. His curve is much harder than usual, has a sharp downward bite and has primarily 12-6 movement. His fourseam fastball generates more whiffs/swing compared to other pitchers' fourseamers, has some natural sinking action, has well above average velo and results in somewhat more groundballs compared to other pitchers' fourseamers. His slider (take this with a grain of salt because he's only thrown 5 of them in 2022) is basically never swung at and missed compared to other pitchers' sliders, sweeps across the zone and is an extreme flyball pitch compared to other pitchers' sliders.