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The new, patient, Eddie Rosario

Minnesota Twins Talk Today, 06:40 AM
An interesting tidbit. We all know that walks aren't entirely indicative of plate discipline, but Rosario's new approach is startling whe...
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Game-Thread 8/14: Kansas City Royals (8-11) @ Minnesota T...

Minnesota Twins Talk Yesterday, 10:30 PM
Catch-Up How did you all enjoy your day off? I'm sure the Twins did. Buxton is playing arguably the best all around baseball of his caree...
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Where are they now? Ex-Twins in 2020

Minnesota Twins Talk Yesterday, 10:30 PM
I said in the 2019 thread that I would start this forum thread...    Let's start populating it. How many former Twins are on ro...
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2020 Game Thread Intros

Minnesota Twins Talk Yesterday, 10:30 PM
Yes, I believe there will be baseball! Further, the Twins would be a popular pick this year to advance to the playoffs and maybe, just ma...
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Miguel Sano's Moonshot

Minnesota Twins Talk Yesterday, 01:46 PM
I finally figured out where Miguel Sano's home run from last night landed.     Moon bomba!!!
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Trevor May, Sliders, and Slime Mold

The last two months of 2019 saw Trevor May emerge as a dominant set-up man in the Twins’ bullpen. From August 1 through the end of the season, May not only had a 1.38 ERA, but held opponents to a pathetic .125/.181/.273 batting line. He fanned 34 of the 94 batters he faced, and walked just six. Of the 333 pitchers who threw at least 300 pitches during that span, May allowed the fourth-lowest weighted on-base average.
Image courtesy of © Bob DeChiara-USA TODAY Sports
As I documented at Baseball Prospectus last May, May turned a corner partially because he changed the grip on his slider, turning it into a harder version of his curveball instead of the cutterish offering it had previously been. However, that doesn’t mean that the slider itself fueled his newfound dominance. In fact, even at season’s end, he hadn’t found a consistently above-average breaking ball.

Trevor May, Slider and Curveball Stats, 2019

Attached Image: Screenshot 2020-07-08 at 8.28.19 PM.png

A good breaking ball should induce swings and misses at about half again the rate at which May’s do so. He showed the ability to reshape both pitches, and to spin them at a high rate, but he got no real results with either pitch.

What changed, then? To answer that, let’s change the subject for a minute. In 2006, biological researchers at the University of Sydney performed an experiment on plasmodial slime mold. Slime mold is, most of the time, a single-cell organism, but under the right conditions, it can form a kind of glob large enough to be visible to the naked eye. It likes to latch onto and eat oats. As you might guess about something that goes by the name “plasmodial slime mold,” it doesn’t like light.

The researchers first put some slime mold into a petri dish with oats at opposite ends, one with an ultraviolet light shining on it and one in relative darkness. The slime mold “chose” (it doesn’t have a brain, but we can call this behavior choosing for these purposes) the oats at the dark end of the dish, over and over again, in repeated experiments. Then, the researchers added more oats to the end where the light was. At a certain point, the greater amount of available food balanced out the aversion to light, and the slime mold began choosing the oats in the light half the time.

One more twist, then we’ll get back to May. The researchers then added a third option for the slime mold: a smaller amount of oats in another dark end of the petri dish. The amounts in the original dark and light ends of the dish were held where they had been, the point at which the slime mold had shown roughly equal preference for the two options. The mold should have been expected to change almost nothing; the new option was clearly undesirable and irrelevant. That’s not what happened. Adding the extraneous, irrelevant option led the mold to choose the smaller quantity of oats in darkness (though still a larger quantity than the new option) three times as often as the larger quantity in the light.

Again, slime mold doesn’t have a brain. Yet, it’s stunningly capable of irrationality, just the way humans are. May, as it turns out, is capable of the same thing. Changing the slider grip gave him two theoretically workable breaking balls. Neither actually worked, but by adding an irrelevant option to the mixture, he disrupted the overall balance of his pitch mix.

Trevor May, Pitch Usage by Month, 2019

Attached Image: Brooksbaseball-Chart.png

This is how May started mowing down opposing hitters like they were novice players of one of the video games he plays so well. He started pumping in his fastball about 70 percent of the time, getting pop-ups and empty swings by the bushel. May throws hard, generates good backspin, and achieves good carry on his heat because of his high arm slot. As he began throwing that pitch more often than ever, he found the success that eluded him as he tried to get his changeup, curve, and slider just right over the previous few years.

It will still help if May comes into this shortened season with a breaking ball that performs the way he’d hoped one would last year. By the end of the season, the slider and curve had melded into each other in a way that ate into the effectiveness of each. If he remains as reliant on his fastball as he was down the stretch, he’ll remain vulnerable to home runs at inopportune moments. Hitters also might begin to sit on his fastball and start laying off the ones above the strike zone.

For now, though, May has turned into a monster, and instead of doing so by finding a great secondary offering, he did it by turning toward what had been his best bet all along—all thanks to his inability to maintain static preferences after the addition of an irrelevant alternative.

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Trevor May is one of two Twins I want to see the Twins extend before the end of the season. I want him remaining in the Twins bullpen in 2021, 2022 and beyond.


The other Twin is Jake Odorizzi. Also want to see them bring back both Cruz and Hill, assuming they have good years and don't retire. But those both should be one year contracts that can be worked out after the Series.

    • Joey P likes this

I love slime molds.As a biologist I watch for them in the woods and I had to read this article because of them - not Trevor.But if Trevor likes this share this video  https://youtu.be/Nx3Uu1hfl6Q and if you are curious - watch and enjoy. 

Dave The Dastardly
Jul 09 2020 07:38 AM

I read this thinking the author was going to reveal that May was loading up the ball with slime. I'm not sure if I'm disappointed or relieved. Confusing times these.

    • Doctor Gast likes this
Doctor Gast
Jul 09 2020 12:18 PM

Interesting comparing slime to May but you got your point across 

This was a very informative posting - I loved the slime mold counterpoint!


I’m so happy that real baseball is here, so that it can foster fine writing like this, because the articles across the last four months were hard to read...

James Rivah Twins Fan
Jul 10 2020 03:33 AM

Loved the slime mold reference! Trevor has definitely turned into a weapon and let's hope he stays on that track this season.

I should have known better than to read this article while eating lunch .... :-)


But actually, I kind of enjoyed it.