Diamondbacks free agency: Each new reliever's most dominant pitch
Miguel Castro: Slider
Adding Miguel Castro to the bullpen was a sneaky good move for the Diamondbacks this offseason. The veteran relief pitcher has enjoyed back-to-back solid seasons. In 2021, Castro recorded 9 holds and posted a 3.45 ERA over 70.1 innings with the Mets. For 2022, he switched teams but stayed in the same state. For the Yankees, Castro went 5-0 with a 4.03 ERA across 29 innings…
Most relief pitchers have at least one nasty pitch that will make a hitter look like they have never played baseball before; for Castro, it’s his slider. In 2021, Castro’s slider recorded a -7 run value and hitters averaged .131 and slugged .222 against it. Utter dominance. His slider wasn’t as dominant in 2022 but he still got hitters to average .189 against it. A possible reason for the drop in effectiveness is that Castro threw his slider 9% more in 2022 than he did in 2021. Obviously, the more hitters see a pitch the better they will adjust to it. Despite this, Castro still has a dominant off-speed pitch that will make hitters look silly. He will be an excellent addition to this bullpen that struggled mightily last season…
Andrew Chafin: Slider
A new addition yes, but Chafin is a familiar face in Arizona. Chafin broke into the league with the Diamondbacks in 2014 and spent 6 full seasons with the club. For the last two years, the sheriff has been dominant. In 2021, he pitched 68.2 innings between the A’s and Cubs and recorded a 1.83 ERA. In 2022, he pitched 57.1 innings with the Tigers and recorded a 2.83 ERA…
Like Castro, Chafin’s best pitch is his slider. In 2021 his slider recorded a -6 run value and hitters averaged .092 against it. In 2022 his slider recorded a -4 run value and hitters slugged .127 against it. Good luck…
Scott McGough: Splitter
McGough has been pitching for the Yakult Swallows of the Japan Central League for the past four seasons. Over his final two seasons with Yakult, he had a 2.44 ERA in 118 innings and recorded 69 saves. He was a huge piece of the puzzle for getting Yakult to the Japan world series last season…
In an interview this off-season, McGough told MLB Radio on SiriusXM that he “Kind of took in the culture, just tried to pitch and listen to their pitching coaches, and they really helped me with my splitter. That’s been the difference for me.”