Chicago White Sox
Jonathan Heasley has thrown 4,474 pitches that have been tracked by the PITCHf/x system between 2021 and 2025, including pitches thrown in the MLB Regular Season and Spring Training. In 2025, they have relied primarily on their Curve (81mph), Slider (86mph) and Fourseam Fastball (94mph).
In 2025, compared to other RHP:
Their curve (take this with a grain of salt because they've only thrown 6 of them in 2025) results in more flyballs compared to other pitchers' curves, has a sharp downward bite and is slightly harder than usual. Their slider (take this with a grain of salt because they've only thrown 5 of them in 2025) generates an extremely high number of swings & misses compared to other pitchers' sliders and is an extreme flyball pitch compared to other pitchers' sliders. Their fourseam fastball (take this with a grain of salt because they've only thrown 3 of them in 2025) is basically never swung at and missed compared to other pitchers' fourseamers, is an extreme flyball pitch compared to other pitchers' fourseamers, has less armside movement than typical, has some natural sinking action and has essentially average velo.