Let’s Talk About Kodi Whitley

Earlier this week, Aaron wrote about the team’s startlingly deep relief corps (https://www.vivaelbirdos.com/2019/11/20/20973930/the-2020-bullpen-depth-chart). I must confess, I was a little frustrated: I’d tabbed that as my own topic for this week, and he did it better than I would have. Instead, though, I’d like to take a short, deep-ish dive into one of those relief prospects today.

I’m overjoyed to report that I’ll be contributing the Cardinals player profiles to the 2020 Baseball Prospectus Annual. When we finalized my list of 68 players to talk about, there were 67 players I’d heard of before. The 68th? Kodi Whitley. It’s not an exaggeration to say that I’d never heard the name, which is phenomenally rare in this modern era of prospect clutching and 50-deep farm system reports.

More or less concurrently with my first seeing his name, Whitley was sent to the Arizona Fall League. It was well-deserved after his frankly ridiculous 2019. He wasn’t really a strikeout artist before this year -- and then he overwhelmed Double-A. His 1.83 ERA was tremendous, and it was backed up by the peripherals; a 27.9% strikeout rate is awesome, a 7.9% walk rate is great, and a 3.17 FIP will play for sure. Then he went to Triple-A and improved every number; 28.1% strikeouts, 4.2% walks, and a 2.02 FIP/1.52 ERA combination.

From scouting the stat line alone, it’s clear that Whitley had a great year. He shoved in Fall League as well, posting 13 strikeouts and only one walk in 11 innings. Relief types aren’t usually huge prospects, but Whitley’s numbers were just that good, and even if that’s all we had to go on, he’d be an intriguing name for 2020 a year after being on no one’s radar.

But that’s not all we have to go on. Scouts were in on Whitley this year -- his velo and spin took a step forward, and he started missing a lot of bats. You can hack together the whiff rate if you’re willing to wade through minor league data -- he got whiffs on 30% of opposing swings, in case you’re wondering, which would have been third-highest among major league Cardinals behind Giovanny Gallegos and Jack Flaherty, not that you can make a straight comparison between minor and major league whiff rates.

But the stuff was still a mystery. There’s no public database of minor league pitch types and velocities, no Statcast for prospects. Or there wasn’t, at least, until Whitley went to the fall league. There, his pitches were captured for posterity. And because of that, I’m going to do an incredibly irresponsible thing and compare each of them to existing major league pitches based on movement profiles.

First, we’ve got the fastball. That’s what put him on the map, and you can see why. The velocity will play -- he sat 95-96, which is several cuts below Jordan Hicks but still good. The juice, though, is in the movement. On average, Whitley got 10.2 inches of ride on his fastball. 10.2 inches is just a number, of course, and picturing a slightly shrunken Subway sandwich as how much a fastball moves isn’t all that helpful. But it’s a lot! That movement would put him in the 95th percentile among all four-seam fastballs in the big leagues last year.

From there, I went to the tape to look for a fastball that most mimicked Whitley’s. I used only vertical break, horizontal break, and velocity. Clayton Kershaw, for example, gets similar ride. But his pitch is almost straight up-and-down, with no horizontal break, and he throws it much slower. So he’s out.

Here’s the list (sorry for the awful graphics, Chorus is a bit broken so I’m improvising):

That last column is a bit of an esoteric metric. It’s Pitch Info’s Pitch Values per 100 pitches. In simple terms, they look at the outcome of every pitch, taking count into consideration, and assign it a value in runs. A positive number means that the pitcher saves that many runs relative to league average per 100 of that pitch they throw. Values around 2.0 generally lead the league when it comes to fastball value.

The point of this isn’t to say that Whitley has a finished major league pitch, because that’s not how it works. But his fastball wouldn’t look out of place among the most dynamic fastballs in the majors. It’s a good pitch right now, one that could propel him to the major league bullpen if he can pair other stuff with it.

About that other stuff. Here’s his slider:

These comps aren’t as good, in two ways. First, they’re not as comparable to his pitch. Sliders these days tend towards sharp and low on break or big and bendy, while Whitley is somewhere in between. Parsons, Carrasco, and Conley are all reaches; there simply aren’t many pitches that match Whitley’s. Second, none of the results are stellar; this isn’t the kind of standout pitch that could carry someone.

Last, there’s his changeup. It’s nearly sui generis; people don’t throw changeups with this much rise, and those that do certainly don’t throw it with this much velocity. These comparisons are necessarily approximate, and I’d love to see more pitch-level data or video of the change to know what’s going on:

These comparisons can hardly be called close, and they’re a tremendously mixed bag. Three are good, one is awful, and Doolittle only threw around 60 changeups last year, so it’s hard to make anything of his. Whitley’s changeup is bizarre, is the point.

What does this all mean? It’s still a mixed bag. Whitley’s fastball is real, there’s no doubt of that. The pitch would look at home at the back of a bullpen. It’s got beguiling ride, and it comes in too fast for comfort. That pitch alone makes him an intriguing relief prospect, and it’s absolutely the reason that scouts like him.

The other pitches are weird, though. His delivery looks funky in the limited video looks I’ve seen, which probably helps out with the deception there. I’d put it somewhere in between Josh Collmenter and Oliver Drake, and that is about as weird as it sounds. But you can’t really look at them offhand and say whether they work or not; it’s going to be a matter of watching and discovering.

At this moment, I’d give Whitley maybe a one-in-three chance of starting next year on the big league roster. There’s always space for relievers with live fastballs, and he absolutely qualifies. It’s just somewhat mind-boggling to me that he got this close to the show before attracting a lot of notice. Hopefully this will be helpful to you in terms of not being caught by surprise when he turns up in spring training.