Kansas City Royals
Stephen Kolek has thrown 4,042 pitches that have been tracked by the PITCHf/x system between 2023 and 2025, including pitches thrown in the MLB Regular Season, The World Baseball Classic, Spring Training and Fall/Winter Ball. In 2025, they have relied primarily on their Sinker (94mph), Slider (84mph) and Fourseam Fastball (94mph), also mixing in a Cutter (91mph) and Change (87mph). He also rarely throws a Curve (80mph).
In 2025, compared to other RHP:
Their sinker has heavy sinking action, results in somewhat more groundballs compared to other pitchers' sinkers, has slight armside run and has slightly above average velo. Their slider has some two-plane movement. Their fourseam fastball has heavy sinking action, has essentially average velo and results in somewhat more groundballs compared to other pitchers' fourseamers. Their cutter has little cutting action, has slightly above average velo and has some natural sink. Their change dives down out of the zone, generates a very high amount of groundballs compared to other pitchers' changeups, is much firmer than usual and has slight armside fade. Their curve (take this with a grain of salt because they've only thrown 2 of them in 2025) is basically never swung at and missed compared to other pitchers' curves, results in more flyballs compared to other pitchers' curves, has a sharp downward bite and is slightly harder than usual.