Seattle Mariners
George Kirby has thrown 8,257 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 Fourseam Fastball (96mph), Sinker (96mph) and Slider (87mph), also mixing in a Splitter (86mph). He also rarely throws a Curve (84mph) and Cutter (94mph).
In 2025, compared to other RHP:
Their fourseam fastball is an extreme flyball pitch compared to other pitchers' fourseamers, generates more whiffs/swing compared to other pitchers' fourseamers, has some natural sinking action, has well above average velo and has slight armside run. Their sinker generates an extremely high number of swings & misses compared to other pitchers' sinkers, is an extreme flyball pitch compared to other pitchers' sinkers, is blazing fast and has slight armside run. Their slider sweeps across the zone, has exceptional depth and generates fewer whiffs/swing compared to other pitchers' sliders. Their splitter (take this with a grain of salt because they've only thrown 13 of them in 2025) has dives down out of the zone, is an extreme flyball pitch compared to other pitchers' splitters and is slightly firmer than usual. Their curve (take this with a grain of salt because they've only thrown 5 of them in 2025) is thrown extremely hard, has an exceptional bite, is basically never swung at and missed compared to other pitchers' curves and results in more flyballs compared to other pitchers' curves. Their cutter (take this with a grain of salt because they've only thrown 4 of them in 2025) is thrown at a speed that's borderline unfair, generates an extremely high number of swings & misses compared to other pitchers' cutters, is an extreme flyball pitch compared to other pitchers' cutters and has little cutting action.