So, what could Junk improve upon this season? Junk had something he wanted to investigate.
Near the close of last season, a FanGraphs writer asked him about the variability of his arm angle at release—variance he was unaware of then. He declined to answer the question, not to be impolite or difficult, because he was unaware it was a thing with him. He was immediately curious.
“I did feel different when I reached back for that 96, 97 or whatever. It looked different,” Junk told me last week as he reflected upon the question. “I feel like I’m throwing it, you know, sidearm… It felt like I was dropping.”
While he could pop the occasional 96 mph four-seamer, he sat 92-93 mph for the majority of his outings. He was curious if he could cruise nearer his peak velocity. It was important to find another level.
After all, consider the average right-handed starter’s fastball velocity is 95.1 mph this season. In fact, the average is greater than that of right-handed relievers (94.9). If a pitcher is below that benchmark for velocity, he’s already fighting an uphill battle. Junk’s average fastball was 93.6 mph last season.
But there was reason to believe he was leaving meat on the bone.
Pitchers’ ranges of velocity are shrinking during the pitch-tracking era—from a 7.37-mph gap between seasonal individual max and minimum fastball velocities in 2008 to a record-low 4.92-mph range last year. Junk’s range was well above average last year (6.2 mph).
When he arrived back in Seattle after the season, he asked Driveline analysts to investigate. Sure enough, they found he had more variability than the average pitcher in regard to his arm angle at release. It was affecting his stuff, creating a wider range of velocity and movement.
Once those numbers validated the issue, and after completing his usual end-of-season motion capture and strength testing, Junk wanted to immediately focus on reducing the variability. Could he more often access his best stuff?
What he found in the lab was that his arm slot lowered when he rotated faster and moved down the mound in a certain way.
“Before, I felt like I would get stuck, like ‘OK, leg lift, and then drop,’” Junk said of his motion sequence. “I always see my velocity drop whenever I get very mechanical, and kind of slow on the mound. Now, it’s just more like leg lift, and then I’m driving down the mound. It’s ‘How quickly can you move?’… Moving fast is a big cue for me.”
When he moved faster, his arm angle dropped. His efficiency and ability to repeat improved.
To hard-wire the new, faster throwing motion into his muscle memory, there was a package of drills Driveline director of pitching Connor White prescribed.
There were pivot picks—but not just any pivot picks—a variant where Junk focused on using the rotation of his body to pull the arm into his optimal slot. There was a focus on athlete movements such as making throws from a shortstop position.
The change wasn’t built around any magic bullet new drill or exercise; it was driven by a different mix and intensity.
“Ideally, you’re increasing the efficiency, and that’s what we’re working on with guys when we’re in the lab,” White said. “We can optimize movement to raise the ceiling and the floor.”
Junk again threw game-like bullpens with the Intended Zones Tracker measuring his command.