https://community.fangraphs.com/solving-adam-ottavino/
When Ottavino’s sliders miss glove-side to lefties, they hang up, right in the middle of a lefty’s bat path. Ottavino’s other big miss is a yanked slider, which has become the root cause of his walk rate. It is a different story for righties; when Ottavino misses the initial glove-side target, the slider is still far enough away from a righty batter (in most cases) in which they would either swing right over it, make weak contact to the right side, or take it for a ball. Despite having 8.1 inches above average of horizontal break, Ottavino has had a -6 run value from his slider in 2021.
If you look at Ottavino’s best years from an ERA standpoint, you notice that his two seasons with the Yankees in 2018 and 2019 were elite. A critical difference between those campaigns and the current one is his pitch repertoire. Although most of it has stayed the same, he has almost stopped throwing his cutter entirely. In 2018 and 2019, he threw his cutter 9.8% and 13.8%, respectively. In 2021 he has thrown it just 1.9% of the time. This is notable because his cutter is essentially a shorter, tighter version of his slider that would seemingly be easier to control. On top of that, in 2018 and 2019, his cutter produced a whiff percentage of almost 50% and nearly 40%, respectively.
Also, in 2018 his cutter had 6.1 horizontal inches of break, or 3.6 inches above average (143% break above average). It wasn’t nearly as good in 2019 but was still respectable at 3.2 inches of horizontal break, 1.2 inches above average. Ottavino has thrown his cutter 20 times in 2021 and it has had a similar break to 2019.
If Ottavino were to increase his cutter usage, he could have a complementary put-away pitch that could be an excellent 1-2 punch when combined with a slider that fools batters. Given that they move in the same direction, hitters would have to make an early decision whether to swing based on whether they think the ball will stay in the zone or not.