It was 84 degrees in Cleveland by the time Michael Fulmer, Detroit’s starter for a September 15 rumble with Cleveland, hit the showers without recording an out for the Tigers. Cleveland won that game 15-0, and Fulmer missed his last two scheduled starts of the season with a knee injury, apparently sustained in-game, that put him in surgery five days later. It was a fitting end to the 25-year-old’s 2018 campaign. Detroit had hoped, at the very least, that Fulmer would be effective enough to stabilize an aging rotation, one in which he and 27-year-old Matthew Boyd were the only starters under 30. At best, they’d reportedly hoped he’d be good enough to spin off to a contender at the trade deadline. He was neither, and instead posted the worst season of his three-year career.

Michael Fulmer Had a Bad Year Season Age IP K% BB% ERA- FIP- WAR 2016 23 159.0 20.4% 6.5% 72 87 3.0 2017 24 164.2 16.9% 5.9% 87 83 3.5 2018 25 132.1 19.7% 8.2% 110 105 1.4

I’d like to focus on Fulmer’s disappointing 2018 campaign for a moment because its presumptive cause — injury — means that a resurgent Fulmer, if he indeed rebounds next year, will probably look quite different than the young man who won 2016’s AL Rookie of the Year award and was an All-Star in the next season. If baseball’s beauty lies in part in the opportunities it gives its players to reinvent themselves, then Michael Fulmer is a prime candidate for reinvention, and with his success or failure rides some portion of the future success or failure of the Tigers. Other pitchers have reinvented themselves after early-career injuries effectively, and I’m always curious to see how they choose to fight their way back.

Fulmer’s health troubles started with the oblique strain he suffered in mid-summer 2017, continued with elbow neuritis that required surgery a few months later, and reached a denouement with the knee injury sustained on the 15 of September on that hot day in Cleveland. Those maladies advanced in parallel with a steady decline — by an inch and a half a year for two years — in Fulmer’s vertical release point, which may be linked to ongoing numbness and tingling in that pesky nerve that required elbow surgery back in 2017. Here’s Fulmer throwing a two-seam fastball against the Indians back in 2016:

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And here’s Fulmer throwing a two-seam fastball against the same team in 2018:

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The comparison is admittedly somewhat hamstrung by the slight change in camera locations between the two GIFs, but I think there are two things are worth noting. First, in the 2016 pitch Fulmer’s upper body is somewhat more upright at the point of release than it is in 2018; second (and somewhat more subtly) the angle between Fulmer’s belt-line — roughly horizontal to the ground, in both GIFs — and his shoulder and upper arm is far more pronounced in 2016 than it is in 2018. Taken together, the two adjustments created a fairly significant drop in the effective release point of Fulmer’s pitches (here’s the Brooks data, for the graphically inclined) that, unfortunately, also has the effect of making those pitches somewhat easier to see, especially for right-handed batters. Here’s a chart that plots Fulmer’s ERA and hard-hit rate in rolling 15-game increments from 2016 to the present. He hurt his oblique in the early summer of 2017:

The challenge for Fulmer going forward will be finding a delivery that maintains the relative effectiveness of his three primary pitches — a fastball (he throws both a four-seam and a sinking variety), a slider, and a changeup — while avoiding undue pressure on either his elbow or his knee. In comments to the Detroit News late last month, Fulmer appears ready for the task:

“We will have to tweak something,” Fulmer said. “Just the way I drive off my back side, my back leg, something isn’t right. My knee doesn’t like it. After these surgeries, we are going to have to find a way to tweak some things. That’s why I am going down (to Lakeland) early again. I want to find a way to fix this thing before everybody else gets down there.”

The Tigers appear to be somewhere between two and three years away from having a good team again, and so a successful future for Michael Fulmer, if it happens, will probably not happen in Detroit. If he’s pitching well by the end of June, he’ll be spun off to some division leader, there to spin out his next three years to free agency. If he’s pitching poorly, there’s no harm in continuing to give him starts in a rotation that lost Francisco Liriano and apparently expects to find some time this year for Matt Moore. One of the cruelties of baseball’s current labor structure is that any upside Fulmer realizes before 2023 is the Tigers’ to keep and exploit, and not Fulmer’s. Fulmer will have to hope the changes he makes this winter are durable enough to last him in good stead until he can finally test the open market three years from now.

For the time being, I’m curious to see what kind of pitcher the 2019 version of Fulmer will be. His old elbow and his old knee got him to the big leagues. His new elbow and new knee will need to keep him there, and there are a thousand ways in which they might do so. Bring on baseball.