St. Louis Cardinals
Although they have not thrown an MLB pitch in 2026, Riley O'Brien threw 3,301 pitches that were tracked by the PITCHf/x system between 2021 and 2025, including pitches thrown in the MLB Regular Season and Spring Training. In 2025, they relied primarily on their Sinker (98mph), Cutter (90mph) and Slider (83mph).
In 2025, compared to other RHP:
Their sinker is a real worm killer that generates an extreme number of groundballs compared to other pitchers' sinkers, is thrown at a speed that's borderline unfair, has slight armside run and has some natural sinking action. Their cutter has heavy sink, generates a high number of swings & misses compared to other pitchers' cutters, has slightly above average velo and has strong cutting action. Their slider generates an extremely high number of swings & misses compared to other pitchers' sliders, is a real worm killer that generates an extreme number of groundballs compared to other pitchers' sliders, sweeps across the zone and has exceptional depth.