Trekking Down Kirby Regret Road, We Come To Adam Mazur

A detailed breakdown with video of Adam Mazur by Nate Handy.

By: Nate Handy

Following the 2021 season, I braved a top 100 pitching prospect rank, sharing observations on execution, development, and stuff. I regret it, I slapped #26 next to George Kirby’s name. Not because I want my ranks to age better, but because Kirby is turning into exactly what I want my pitching prospects to be; (at the time of writing): 4th in the bigs in WHIP, 9th in quality starts, 11th in ERA, 36th in wins, and 37th in strikeouts, over 26 starts. Kirby is 25 years old, proving the stamina for the MLB marathon, adapting his repertoire, and heading into his third season in 2024 looking like one of the young, well-rounded talents with top-shelf pitch execution I feel good about over the long haul. Preaching to myself over and over to not miss on my types, how did I do it here? There's no way 25 arms fit my bill better than Kirby back then.

“#26 George Kirby” has eaten at me. This is undeniable. Trying to take away lessons, I found myself at last year’s FYPD tables with a proverbial, “don’t leave without Adam Mazur” notecard stuffed in my pocket. Kirby regret played into a lot of that. Fast forward to September, and it feels like a good time to binge-watch and have a little state of the Mazur. Does the pre-FYPD evaluation match the video? Did we pile regret atop regret? Are there similarities between the two pitchers? Do I have any clue what I’m doing?

Of course, as a first-year player I spent highly on, I’ve been keeping tabs, watching at least portions of all his broadcasts, but here are the notes from the six starts I decided to really get into (link).

Control and command

This was almost always the lead story with Kirby, garnering 70-grade control reviews by some. Reviewing Kirby’s back half of 2021 for the mentioned ranks, I came away feeling his command grades were overselling him, thinking he was a really good strike thrower, but strike throwing isn’t always the same as command. Of course, now, Kirby has some of the best execution in the world. He gets the baseball to do what he wants at as high a clip as anyone. Now I’m no year-long follower of amateurs, but I spend a lot of time prepping for FYPDs and watching as much as possible throughout the year of select players. My assessment was Mazur showed the best command of the class’ arms I spent time on.

Watching Mazur today, I can’t help having similar feelings I had about Kirby back then. His strike-throwing is great, 68% on the season. Yet, I wouldn’t call his command great, or at least the entirety of the arsenal. Portions of it are far from great. Yet, considering the 40 to 55 control grades out there, he may be getting undersold in this regard. Mazur’s throwing even more strikes of late, 70.38% since hitting AA (6 GS). 

Yet, when it comes to command, Mazur’s a little trickier to figure out. He hits the plate at a high rate, but I’m not quite sure how great he is hitting the parts of the plate he wants. And plenty of pitches I’d deem not MLB-caliber earn strikes, both called and swinging. Further complicating matters, as odd as it may sound, Mazur has stretches he seems to lack nuance in his location selections. I dare say he offers too many generic strikes, and since his control is so good, particularly with the fastball and intermittently with the slider, there are a lot of middle-middle offerings. This reminds me of 2021 Kirby and his fastball, and part of what I dinged him for. Both though, perhaps due to the quality of offerings, get away with working like that at this level with mostly favorable results.

Mazur’s secondary control/command isn’t near the same level as the fastball but does have its moments. Mazur has stretches he really is putting the ball on a dime. He also has the propensity to double up on an idea after he misses one he doesn’t feel good about. And impressively, he typically nails the execution the second time. Mazur also has a knack for following up a decent offering with juuuust a bit better one of the same. I dig all this, not because it’s some unheard-of trait, but rather because he consistently does it. Here’s some looks at what I’m talking about:

After getting down 2-0, he puts this 2-1 slider where he wants, then delivers the kill with an even better 2-2 location his catcher asked for.

Spikes one and then gets right the next pitch for a whiff.

The next hitter he goes sld/sld?/sld for the K. He was feeling the slider this inning.

Vs. Kevin Alcantara to start the inning he misses with a 0-0 slider (Mazur doesn’t try getting chase 0-0, or ever really, so I think it’s safe to say he wanted this to catch plate), and then he gets his strike. The second offering points to what I was saying about generic strikes, but it appears he rebounded to get the baseball to do what he wanted here.

Another “get it right” double-up.

And here are a few double-up examples whereupon the second try got better, but were still probably not truly where he wanted them being ahead in the count like he was:

Mazur won’t get away with those last two locations nearly as much as he does now, in the bigs. Mazur tends to get fine results with breaking ball misses up in the zone, but that’s a precarious game in the bigs.

(This is a very hard thing to speculate on from my vantage point, but there are times it’s impossible to discern if Mazur intends to land some breakers up. I also wonder if there’s an occasional cutter sitting a tick or two harder than the slider at 90mph.) Here are some breakers in bad spots:

To be fair to Mr. Mazur, cutting up a bad slider montage is harder with him than most. The majority of the above were 0-2 or in counts he had the hitter dead to rights, thus exuding fine examples of him not being able to get the baseball to do what he wanted. And if you think I may be being a bit too critical of him, you bet I am. My FYPD plays, I made, were Mazur over Cade Horton. And again, I had a Kirby-esque dream in my head.

The Fastball(s)

Mazur’s two-seam and four-seam fastballs consistently sit in the 94-96 range. As you can see, he’s got a wiry explosive frame which begs a fair question if there’s more coming, and I’m not the only one wondering such things. He’s just a tick/tick and a half slower than Kirby velo at this juncture. There are also reports Mazur’s hit the high 90s. The command and use of the fastball are very Kirby ‘21-esque as well, pumping plenty of strikes with it and flashing pinpoint command. Perhaps what happened with Kirby, will happen here too…as the level of hitter increases, simply pumping the fastball for strikes is going to need a touch of creativeness. We won’t get into the fastballs as much as we did the slider, but here’s a look at some fastball kill shots:

I do believe there is a smattering of a two-seam and four-seam fastballs in there. Here’s a good morning, good afternoon, good night, two-seam 96/two-seam 95/four-seam 97 per broadcast gun for Caleb Roberts.

(The four-seamer was not where he intended, but it got the job done.)

Nine of Mazur’s 28 strikeouts in these six outings were via fastball, while the slider accounted for fourteen, the changeup four, and the curveball one.

What is this?

This slipped into the fastball montage before I caught it, but this is Mazur getting B-side Dalton Shuffield on a 1-2 changeup. When we got velocity graphics this offering sat 5-6 mphs slower than the fastball, sometimes touching 90s. Not what is said to be the ideal velocity differential. That’s more landing in a styrofoam pit than pulling a parachute.

Kirby’s changeup isn’t his strongest pitch either. He only throws it 2.1% of the time and only against left-hand hitters who are batting .500 against it. The offering garners only a 15.7 CSW%. Kirby’s developed a splitter as well, at least according to Savant, which they say he throws twice as often, again to lefties, garnering a 25.7 CSW%. Here are the two pitches’ heat maps:

Now checkout where Mazur tends to land his:

Leaving it up or over the heart is typical. Two of those accounted for half his strikeouts with the pitch too. It’s not to say he can’t occasionally put it in a more sensible spot, but it’s not often:

You’ve seen the four strikeouts from the changeup now. An 89/90 mph change that gets left up or over the middle of the plate doesn’t leave me feeling good about it being a major league weapon. Mazur has gotten away with a lot of bad ones, while surprisingly having alright results. There does seem to be something about it tough on hitters, but my guess is, as a backed-up slider can catch hitters off guard and fetch positive production, Mazur’s changeup results feel similar. Surprisingly, I only spotted two, maybe three hits off the change over the six outings. He doesn’t throw it nearly as often as the fastball or slider, but nonetheless. Here is Patrick Winkel hitting a double and a single off it, and a third instance I’m not 100% on, but think it was a changeup:

Mazur’s changeup can be tough to spot, especially during broadcasts without velocity, but at the end of the day, this pitch feels like a project. Surprisingly some have put 50s on it. To Mazur’s credit, he appears to be taking this project on as the usage seems to be increasing. Regardless of how the project ends up going, this is a big plus in my book. It shows stones and is an uptick in the Mussina index score.

When thinking about Bauer’s triangles idea, (link if you’re unfamiliar) Mazur needs a slow gear pitch. The other slow option has warts too.

The Curveball

This offering comes in low-80s and shows shape I’m not so sure about. It’s obvious Mazur doesn’t have as much confidence in it as the slider. There were several times he shook it off to get to the slider. The command needs plenty of work from a North/South standpoint but is pretty good east/west, and it did seem to improve as we moved along. It didn’t show to be a big whiff-getter, but it did garner a lot of mishits and weak contact. Mazur throws it more than the changeup and will offer it to righties more than the changeup. Here are the three hits off it:

(Jacob Wetzel single, Spencer Packard single, Seth Beer double)

And here are a few whiffs earned, which are few and far between:

(0-0 vs Jancarlos Cintron and the lone K, 0-2 to Camden Duzenack)

There are plenty of spiked curves, and the bountiful hung-up ones have gotten a lot of generous passes. Lefties are hitting .255 versus Mazur, while righties are .173. The lack of slow, the lack of off-speed for lefties, is likely playing into this split. But the east/west game with the slider and two-seam can get nasty, and the north four-seam game has teeth. But the slow, more southern weapon just isn’t major league caliber, yet anyways.

Here is an at-bat versus Alberto Rodriguez containing some of the different warts, especially against lefties. Mind you, even when you hunt for a bad at-bat, Mazur still shows some positive things. He misses a nasty two-seamer that probably gets whiffs against a lot of aggressive hitters. Then he earns a generic strike that might be dicey to an MLB lefty with a breaking ball (pretty sure that’s the curve), just misses with another fastball, lands a backdoor slider for a strike that was a miss, can’t delivery a kill, spiking a curveball in the dirt, to give up a weakly struck base hit on well-located fastball. He then struck out the next guy to end the inning:

So What’s The Verdict?

Now, don’t get it twisted here. I am not saying Mazur is Kirby 2.0. Not in the least. I’d never say a 22-year-old needing this kind of polish, whose track record is South Dakota, Iowa, and a handful of double-A starts is going to be one of the best young pitchers in baseball. Mazur’s secondary game is nowhere near Kirby’s. But I also didn’t think Kirby had a chance to Kirby either, and the dream outcome here is similar. There’s a lot of deja vu moments for me with the fastball/slider game. Albeit, I’d say Kirby commanded his slider better than Mazur.

It looks like 100 innings was/is the plan for Mazur, who hasn’t needed Tommy John, and I’ve heard folks reference his frame and how that scares them and all that. Blah blah blah. Pitching speculation isn’t for scaredy cats. We aren’t prowling for every plastic arm capable of 150-200 strikeouts one or two seasons and then never get much again, or some such. We are on the prowl for arms that can produce over the long haul. Sustainable careers around these parts, please. A year on the shelf isn’t gonna deter me from the potential to grow into the best of both worlds…elite command with really good stuff.

Kirby exuded a lack of horsepower to me back then, and I dinged him too much, failing to weigh his coming back from injury appropriately. The point being, any noise about Mazur’s frame and all that…well, I just can’t hear that after Kirby. Even though I had hoped to be more impressed with aspects of Mazur’s game at this juncture, I don’t regret valuing him like I did. To regret such a thing would feel like repeating Kirby mistakes, and we can’t be having that now.

Do I regret going Mazur over Horton? No. Could that change after doing such a review on Horton? Of course. Sure, Horton has 114 strikeouts in 84 innings while Mazur has 86 in 91 innings, but I don’t think it’s out of pocket to think Mazur learning to pitch more creatively in the zone, actually attempting to get batters to chase with two strikes, and perhaps getting another secondary to MLB caliber could increase the K production. Horton’s Double-A K/9 is .30 something higher than Mazur’s. My suspicion is Horton’s already pretty refined in what his game is, whereas Mazur has more developmental meat left on the bone. Perhaps that’s a bad assumption, though. In an alternate world where execution gets valued like “stuff” does in this one, would Mazur be the 4.5M dollar arm and Horton the 1.25M?