Discover how Brad Keller's reinvented arsenal and Detroit's unique pitching infrastructure could unlock his backend starter potential, offering much-needed innings.
When Evan Petzold linked the Tigers to Brad Keller as a potential starter, the first reaction from most Tigers fans was probably disbelief. Keller is 30, coming off multiple uneven seasons, and the version of him that looked like a mid-rotation workhorse in Kansas City hasn’t been seen in years. But Keller’s 2025 profile, when you actually sift through the data, has a few wrinkles that explain why pitching-needy teams will kick the tires.
A veteran who can provide backend support? Why not. Here is more on his statcast data.
STATCAST DIVE
1. The 2025 pitch mix actually tightened into something usable
Keller threw five pitches in 2025, but not in a chaotic way — the usage looked structured:
- 4-Seamer: 42.6%, 97.2 mph
- Slider: 18.4%, 86.7 mph
- Sinker: 14.0%, 94.1 mph
- Sweeper: 13.3%, 81.4 mph
- Changeup: 11.7%, 83.1 mph
This version of Keller isn’t the sinker-heavy ground-baller he was early in his career. He reinvented his fastball profile, leaned harder into horizontal shapes, and tried to generate chase with the sweeper and slider combination.
This..would work in a role where he may be an opener or a swing man out of the bullpen.
2. The movement profile shows distinct shapes — not redundancy
The Savant movement chart tells you why teams think Keller is still tweakable:
- The sweeper carries huge glove-side sweep, up to 18–20 inches.
- The slider is shorter and firmer, living in a different band.
- The four-seamer has modest rise but above-average velocity.
- The changeup maintains separation but doesn’t drift too far horizontally.
This is a mix where refinement matters. Keller to me has a good mix that works on both lefties and righties. He allowed just one home run in 29.1 innings of work against lefties, posting a WHIP of 1.16 and righties, in 40.1 innings of work, a WHIP of 0.82.
Detroit’s pitching infrastructure, which thrives on pairing movement lanes and reducing “dead zones,” would treat Keller like a multi-month project, to extend his innings a bit, not a plug-and-play arm.
3. There are still swing-and-miss ingredients
Some of his individual whiff rates in 2025:
- Slider Whiff%: 26.7%
- Sweeper Whiff%: 46.3% (148 pitches so more than a small sample size)
- Changeup Whiff%: 39.7% (using this on lefties, really damn good)
He may not generate elite swing-and-miss overall, but the ingredients are there if Detroit can isolate which pitch pairings work best. Keller’s K% in 2025(27.2%) was above the league average (22.2%) but the raw characteristics of the breaking balls show more life than his headline numbers. That pairs well with a fastball that had him in the 88th percentile of the league at 97.
4. The Tigers are uniquely positioned to try something different
The rotation needs innings. The depth at Toledo is thin. And the organization has a pattern: sign a veteran, reshape the arsenal, like they did with Jack Flaherty and put him out there among the pitching chaos.
Keller, in his current form, matches that philosophy more closely than higher-profile free agents. He could help this team, even under 100 innings.
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