Jordan Montgomery and the Sinker Renaissance

Jordan Montgomery hasn’t had the easiest of careers. While he established a name for himself with a solid rookie campaign in 2017, extended battles with injuries kept him off the mound in subsequent years. An underwhelming return in 2020 (5.11 ERA) raised questions about his future with the Yankees. But the much better peripherals (3.87 FIP, 3.65 xFIP) signaled a return to form, and the following year, Montgomery put together somewhat of a second breakout season, anchoring a rotation that was considerably more volatile than it is now.
Last year, Montgomery made an adjustment I thought was interesting but never got to write about, drastically raising his four-seam fastball usage in September, which had its pros and cons. On one hand, this newfound reliance on the hard stuff granted Montgomery the highest monthly strikeout rate of his career, as hitters found themselves whiffing at elevated fastballs. On the other hand, it led to a barrage of hard contact; the shape of Montgomery’s fastball isn’t great to begin with, and the corresponding decrease in sinker usage didn’t help, either.
Considering Montgomery’s excellent command, though, I believed he could make this new approach work in the long-term. So naturally, the development we’ve seen this season is… a near-abandonment of the four-seamer! His last five starts all featured a four-seam fastball usage under 10%; against the Tigers on June 5, Pitch Info thought he didn’t throw a single one. But Montgomery isn’t just tinkering with his pitch mix. Check out this side-by-side view of his typical arm slot in 2021 (left) versus 2022 (right):
It’s subtle, but you can see that Montgomery is throwing slightly less over-the-top than before. The Hawk-Eye readings bear this out: he’s lowered his average vertical release point from 6.70 feet to 6.47. What good is a different angle for? My theory is that it’s helped Montgomery exchange vertical movement for horizontal. His sinker is getting more drop and arm-side run than ever before, which is the sort of trade-off stuff models absolutely love (and opposing batters hate). It’s come at the cost of a worse four-seamer, but realistically, improving two diametrically opposed fastballs is a tall order. Montgomery made a choice to stick with one, and so far, it’s worked wonders.
Originally, this article had a much bigger focus on Montgomery. But looking around the league, I couldn’t help but notice several other pitchers who’ve placed a recent emphasis on their sinkers. There are the obvious names, like Clay Holmes and his triple-digit, bowling-ball sinkers, or basically the entire Giants rotation sans Carlos Rodón. Lesser-known examples (to the average fan, at least) include Mitch Keller, who, as noted by Michael Ajeto, switched to a sinker-slider combo after a disappointing start to his season. Oh, and did you know Robbie Ray reintroduced his long-dormant sinker? Wild. Maybe he reckons it’ll help curb the home runs. Read the rest of this entry »