Although he has not thrown an MLB pitch in 2020, Sean Doolittle threw 6,440 pitches that were tracked by the PITCHf/x system between 2012 and 2019, including pitches thrown in the MLB Regular Season, the MLB Postseason and Spring Training. In 2019, he relied primarily on his Fourseam Fastball (94mph), also mixing in a Change (84mph) and Slider (81mph).
Basic description of 2019 pitches compared to other LHP:
His fourseam fastball has much less armside movement than typical, generates more whiffs/swing compared to other pitchers' fourseamers, has well above average velo, results in somewhat more flyballs compared to other pitchers' fourseamers and has some added backspin. His change generates fewer whiffs/swing compared to other pitchers' changeups, has a lot of backspin, is slightly firmer than usual and results in somewhat more flyballs compared to other pitchers' changeups. His slider has short glove-side cut.