Seattle Mariners
George Kirby has thrown 10,706 pitches that have been tracked by the PITCHf/x system between 2022 and 2025, including pitches thrown in the MLB Regular Season and Spring Training. In 2025, they have relied primarily on their Slider (87mph), Sinker (96mph) and Fourseam Fastball (96mph), also mixing in a Curve (84mph). He also rarely throws a Splitter (86mph), Change (88mph) and Cutter (93mph).
In 2025, compared to other RHP:
Their slider sweeps across the zone, has exceptional depth and is much harder than usual. Their sinker is blazing fast, has slight armside run and has some natural sinking action. Their fourseam fastball generates an extremely high number of swings & misses compared to other pitchers' fourseamers, has some natural sinking action, has well above average velo and has slight armside run. Their curve is thrown extremely hard, is a real worm killer that generates an extreme number of groundballs compared to other pitchers' curves, generates more whiffs/swing compared to other pitchers' curves and has a sharp downward bite. Their splitter results in more flyballs compared to other pitchers' splitters, has some natural sink to it and is slightly firmer than usual. Their change is basically never swung at and missed compared to other pitchers' changeups, is much firmer than usual, has slight armside fade and has some natural sink to it. Their cutter (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' cutters, is blazing fast, is an extreme flyball pitch compared to other pitchers' cutters and has little cutting action.