40 in 40: Alex Hoppe, The Contraption Hungers, And You Are Its Sustenance

In mechanical engineering, it’s common knowledge that Contraptions (sometimes referred to informally as “Machines”) are fed by Fodder. The term of venery for an individual piece of Fodder is Pile. Some examples in a sentence: “When new Fodder joins the Pile, it’s better for everyone; The Contraption was beginning to hunger.” or, “Alex Hoppe, The Contraption demands to be fed, and as a recent addition to the Pile of Fodder, you are its chosen fuel, its sustenance, its very lifeblood. Prepare to be Contrapted.”

That, at least, is the hope that anyone who follows the Mariners should have upon reading “Seattle has acquired [pitcher they have not heard of] in exchange for [a minor-league just-a-guy hitter].” The organization has developed quite the reputation as a pitching lab. That reputation is justly earned. From drafting an entire rotation’s worth of MLB starting pitchers in just four drafts to being a career-changing destination for the castaway and the non-tendered, Seattle has proven that they’ve built something special. 

They’ve built a smooth, well-oiled Machine. A Contraption, carefully engineered to take, for example, pitchers like Alex Hoppe and transform them into, for example, pitchers like 2021-2023 Paul Sewald. 

What is a pitcher like Alex Hoppe? Hoppe, acquired from Boston this off-season, is a 2022 6th round draft pick that has steadily risen through Boston’s farm as a pure relief pitcher. He comes without pedigree, never landing on Boston’s top 30 prospects list. He’s mostly been a middle relief guy, only ever recording six saves in a season. He’s achieved mostly acceptable results thus far without ever really excelling. 

There’s almost no easily-accessible video of him besides this one Instagram reel from Boston’s Player Development account.

So, from afar, his repertoire stands out to me as looking almost like the antithesis of modern pitch design philosophy. 

What’s sexy in pitching these days? Low-slot, high-band rising fastballs with an absurd IVB or VAA, if you’re a pronator, or a seam-shifted wake sinker that tumbles if you’re a supinator (or both, if you’re Bryan Woo). Hoppe throws a four-seamer that doesn’t get an insane amount of ride, and given the 52.3° arm angle, has a pretty poor VAA. He also has a cutter that shows solid cut and acceptable ride. 

Also sexy: frisbee sweepers with bonkers horizontal movement and almost no drop, and perhaps even positive IVB. Hoppe throws a sharp, downward 11-5 slider that bites sometimes, but can also be a bit slack-jawed. This means that it overlays with his cutter quite a bit in movement profile. 

As for offspeed pitches, the tumbling, low-spin splitters or the Skenesian splinkers are hot, as is the new “kick change”. Last season, Hoppe sported a new changeup that’s relatively mediocre, and was deployed exclusively against lefties.

Today’s pitch-design landscape feels like an arms race – some team or player builds something new and weird, identifies some trait or movement that makes life hell for hitters, and leans into it. Everyone else follows suit, and suddenly everywhere you look, you’re seeing these new pitches, or new varieties of old ones. Hoppe’s offerings, by comparison, are simple and unextraordinary. 

That isn’t necessarily a problem, but what definitely is, is that he has not demonstrated the ability to control the ball – he ran a 12.3 BB% rate in AA/AAA last season. For a relief pitcher, that is…not good!

At this point, Hoppe is rather raw, but that’s okay. Being polished and already flashing above-average pitches with good stats isn’t a prerequisite for becoming Contrapted. The opposite is probably more true – what makes the Mariners pitching development team so uniquely good at this is their ability to see things that others don’t. 

What do they see in Hoppe? There’s a few things that catch my eye. 

The first major one is that arm angle. His average arm angle of 52.3° is well more than a standard deviation higher than the mean arm angle (about 36° for pitchers with over 300 pitches thrown last season).

This is a chart showing arm angle distribution from MLB last season, controlling for the top 5 outliers on both ends for data cleanliness. Hoppe currently lives in the third right-most of these bars, with an arm angle higher than about 90% of the sample. Not quite outlier-high, but pretty dang high. 

Another thing that catches my attention is that while he ranks quite highly in Whiff%, Chase% and K%, he allows very high exit velocity and Hard-Hit% – he more or less turns batters into Khris Davis. He might be in the category of “effectively wild”. Luckily, because his groundball rate is also exceptionally high, (55% vs 42% average in MLB last season), he hasn’t been punished for that…yet. 

He had a pretty high BABIP last season (.347), which, in the face of letting batters make powerful contact with the ball, makes sense, but it’s also indicates some unluckiness. He also had a generous difference between his xwOBA (.278) and his wOBA (.318), once again showing that he may have underperformed last season relative ot his true talent.

It’s hard for us to say, from the outside, what the keen, hawk-like eyes of The Contraption have identified in Hoppe as ideal sustenance. Perhaps they prize that higher arm angle in a moment of low angles. A lot of the pitchers at the higher end of that spectrum have been raising theirs even further over the last couple of years, and no one on the Mariners besides another relatively new acquisition, Luke Jackson, has an arm angle over 44°. Maybe they’ve identified biomechanical tweaks that could enable him to control the zone, while also adjusting the pitch profile. As a reliever, after all, you’re really ever just one lights-out pitch away from being an impact arm.

If it were any other organization, I would feel silly for thinking this much about a reliever acquired for a 14th-round catcher. It would be safe to say that we simply swapped org guys. It’s still a decently likely outcome. With Seattle, though, it’s hard not to think that he’s been deemed Contraptable, and in a year or two they’ll have created yet another high-leverage bullpen arm out of simple Fodder. 

PS: I’d be remiss if I didn’t include this. Shoutout Sweezo #sweezo