The most dominant pitcher in the minors pitched in the majors. But he didn’t pitch much, as a September call-up, and he wasn’t very good, and you probably don’t know him. He gave up a home run. Walked four and whiffed five. About a hit an inning. He wasn’t handling high-leverage assignments. For all intents and purposes, his big-league work was almost invisible.

And yet, the most dominant pitcher in the minors was extraordinarily dominant, in the minors. He is but 23 years old, and he isn’t going away. He’s not about to change anyone’s offseason plans. He’s not about to get dealt in a blockbuster. He’s a prospect. He’s a prospect who’ll get an extended chance to build on what he’s already done.

The asterisk is up there because “dominant” is subjective. You might have your own preferred indicators. I’ve elected to go with FIP, and I’ve set an innings-minimum of 50 frames. Based just on those terms, here are last year’s five most dominant minor-league pitchers:

Best Minor-League Pitchers
Pitcher IP FIP K-BB% Age
Bryan Valdez 67.2 1.03 33% 21
Jonathan Holder 65.1 1.30 40% 23
Grant Dayton 52.0 1.31 40% 28
Denny Martinez 72.0 1.44 24% 19
Joe Jimenez 53.2 1.67 30% 21

This would seem to call your attention to Bryan Valdez. He is, perhaps, a very good pitcher, but I’ve made another subjective decision. See, Valdez threw all his innings in the Dominican Summer League. It all counts, but I don’t consider that a regular minor-league level. My personal minors extend on down to rookie ball, so that leaves Valdez on the outside looking in. Which means we move on to Holder. You know the name right after him — Dayton carried his minor-league success with him to the Dodgers. Holder got less of a chance with the Yankees, but the better chance is coming. Nearly all of his innings were thrown in Double- or Triple-A.

Holder’s 2016 in the minors was almost too good to believe. Out of everybody who threw at least 50 innings in the minors, only Dayton and Holder pulled off a K-BB% of 40%. Nobody else was above 35%. Somehow, even more unbelievably, Holder generated 35 strikeouts without a single walk in Triple-A. In his final minor-league appearance, he struck out 12 of 13 batters, including 11 in a row. His minor-league OPS allowed was .447; his minor-league OBP allowed was .198. Think of the most dominant reliever you’ve ever seen in the majors. Holder was that guy in the high minors. You can’t keep a pitcher like that down very long.

Holder didn’t come out of nowhere. He was an excellent collegiate closer at Mississippi State, and the Yankees drafted him in the sixth round in 2014. But, in 2014, they tried him as a starter. In 2015, he started another 21 times. He was good enough to run a low ERA, but this past year, it was all relief. Holder thrived upon the readjustment. And, by the way, those 65.1 innings — those came in 42 appearances. Holder had 16 games in which he threw at least two innings. That’s another thing that makes him frightening. He wasn’t amazing for an inning at a time. He was amazing for longer than that. Holder was the Andrew Miller of the upper minors.

For some additional numbers, a table, comparing Holder to the average reliever at his levels (combined):

Jonathan Holder vs. Average Reliever
Pitcher FIP K% BB/HBP% Strike% Contact% Pop-Up%
Holder 1.30 42% 5% 71% 67% 15%
Average RP 3.50 23% 10% 63% 75% 7%

The strikeout and walk rates are already suggestive, but Holder threw better than seven of every 10 pitches for strikes. That’s basically peak Cliff Lee. His pitches were difficult to hit when batters swung, and then you get to the last column. Holder didn’t even need it, but he ran a pop-up rate that was twice the average. A pop-up is effectively a more efficient strikeout. So, if anything, Holder’s strikeout rate was misleadingly low. And he almost never fell behind in counts.

You might wonder how Holder can do this. At 6’2, he’s not short, but he’s also not tall, for a pitcher. He doesn’t get extreme forward extension. It’s a simple recipe: Holder throws four different pitches, and he has pretty good control of all of them. His four-seamer can get into the mid-90s, and it has plenty of rise, with little horizontal break.

Sometimes, Holder turns the ball in his hand and grabs it along the seams. That gives him a second fastball, with a bit of drop, and an extra half-foot or so of lateral break.

As secondary stuff goes, Holder can come at hitters with a sharp slider or cutter. It’s worth noting he didn’t run a bad platoon split.

And, finally, there’s a curveball. It’s a very sharp curveball. According to Baseball Savant, Holder’s average curve in the majors last year had a spin rate of 2927 RPM. That rated him in the 97th percentile, basically tied with Jeremy Hellickson and Lance McCullers. The average curve had a spin rate of 2462 RPM. So Holder does have a quality softer offering.

When I was examining some similar pitches, I saw that Holder’s fastball and cutter are kind of like Alex Colome‘s. But when you think about the whole package, the same name might come to you that eventually came to me. Holder does not throw quite as hard as Wade Davis does, and extra velocity is always important. But Holder was basically just prime Davis in the minors, if the Andrew Miller thing isn’t working for you. Based on handedness and repertoire, Davis is more appropriate, anyway. And he’s the guy you can see when you watch Holder and daydream. Holder could try to do his impression, and the door’ll be open in the season to come.

Could be that Holder is some kind of Quad-A pitcher. Could be, alternatively, he’ll just get hurt, like pitchers do, and that’ll be that. The Yankees are out there looking at high-priced available relievers, and they want someone reliable they can pair with Dellin Betances. But even though Holder can’t be depended on for now, he will get his opportunity. The Yankees know what he might have, and they’re not going to sit on that any longer. There are, most definitely, more exciting pitching prospects. On a per-inning basis, I don’t think there’s a more dominant pitching prospect.