Pittsburgh Pirates: Duane Underwood Jr. May Be Turning a Corner

Despite a tough luck outing on Friday night, Duane Underwood Jr. is off to a strong start this season and may be turning a corner in the Pittsburgh Pirates bullpen

Duane Underwood Jr. has started the season on a high note once again. Five of his six outings have been scoreless appearances, and he has yet to walk a batter either. It’s a small sample size, for the Pittsburgh Pirates reliever and nothing can be taken from the bottom line results, but are there any other metrics that could suggest that Underwood Jr. may have actually turned a corner this year?

In a small sample size like this, pitch data will always paint a better picture than bottom-line numbers like ERA, FIP, or WHIP. Underwood Jr. has significantly changed his pitching repertoire up this year. He’s thrown his cutter 30.6% of the time, which is a slight 3.5% uptick from 2022. Though, two years ago, in 2021, he was using the pitch less than 1% of the time. However, it’s the other pitches in his arsenal that have seen a massive change in usage.

Underwood has pretty much completely dropped his fastball. He’s thrown it just once this year, for a 1.6% use rate, compared to 11.7% in 2022 and 36.1% in 2021. He is using his change-up, sinker, and curveball all around the same rate, at 24.2%, 22.6%, and 21%, respectively. Not only has his pitch usage made a massive change, but the active spin rate of two of his offerings have moved in the right direction.

Active spin refers to the spin that contributes to movement. With curveballs and fastballs, you want this to be up. However, with off-speed pitches and sliders, you want this to be low. Underwood’s cutter currently has a 61% active spin rate. That’s a significant uptick from 51% last year. His change-up is down to 86% active spin rate, compared to 93% in 2022. These are his two most used offerings.

According to Baseball Savant, Underwood’s cutter’s vertical movement vs. average is up to 2.3, a major upgrade from -2.6 last season. He’s also added another inch of horizontal movement to his change-up (though his horizontal movement vs. average has only gone from 0.5 to 0.7). His curveball and sinker haven’t had a major change in movement, or movement vs. average, however.

Have we said something similar in the past? Yes, but there's no denying that he's added more movement and changed up his arsnel once again. I think it's too early to say that he's turned a corner. We have to see if the changes help him in the long run, at the very least, he looks like a changed pitcher.