The Value of a Cutter: Evaluating pitching prospect Hayden Deal

One of the more fascinating story lines so far from the 2019 season down in the minor leagues has been the success of LHP Hayden Deal in High-A. Discovered by long-time Braves scout Billy Best and signed as an undrafted free agent out of college, Deal began his career in the Braves’ system as a reliever. However, in June and July of last season down in Rome, Deal saw some action as a starter, as he made five starts and performed really well in them, with a 1.95 ERA in 27 ²⁄₃ innings. Even more impressive was his 21/2 K/BB ratio and just one homer allowed across those five starts. He didn’t stay solely as a starter in 2018, but it definitely caught our attention, especially given the success the Braves have had in converting Tucker Davidson from a somewhat unknown reliever into a bona fide starting pitching prospect.

At first glance, the known arsenal was okay. The numbers showed that he had a fastball that generally sat in the low 90s and could touch 93-94, with a decent breaking ball. However, it is here where the numbers got deceiving. See, we hadn’t had a chance to see Hayden live as a starter and as it turns out, he has a true cutter... and it’s a good one.

A cutter, or cut fastball, is a pitch that doesn’t quite have the same movement as a slider, but is thrown harder and does have horizontal movement to it. The existence of a cutter in a pitcher’s arsenal isn’t as rare as a guy that throws a palm ball or screwball or something truly odd (among conventional pitches, the cutter is second only to the splitter in terms of rarity), but it is interesting how important it has been to Deal’s success. Since all he has done so far in 2019 is slay opposing batters to the tune of a 1.30 ERA with 38 strikeouts against just 11 walks in 41 ²⁄₃ innings this season, let’s take a look at his cutter and how that could help him down the road in the majors, especially in regards to his platoon splits. As one person within the Braves’ organization said about him, “He cutter against righties is a game-changer.”

I talked to three different scouts about Deal and his cutter and they all had the pitch right at a 55-60 on the 20-80 scouting scale. The pitch has late movement and tunnels really well with his standard fastball (meaning that both his fastball and cutter look the same and take similar paths to the plate). So, he has this interesting and good pitch in his arsenal, how does this help him in any sort of unique way. Well, it has to do with his platoon splits and what cutters do well.

See, one would expect a lefty hurler like Deal to perform well against lefties. That advantage is generally more pronounced than the righty-on-righty matchup. That is shown in the numbers as opposing lefty batters hit just .232 against him in 2018 and are hitting just .200 against him this year. Where things get interesting is his numbers against righties. Right-handed batters hit just .200 against him in 2018 and he has been even better against them this year to the tune of a .181 BAA. Keep in mind that in general, lefty pitchers far worse against righty batters, in accordance with the basic concept of platoon advantage.

Cutters are tricky because, in talking to a couple of lefty pitchers, it is very much a “feel” pitch that, if executed correctly and sequenced well with a pitcher’s other offerings, can act almost like a changeup does for many other pitchers against opposite-handed batters. However, if one doesn’t have consistent feel for it, it can get knocked around especially if the hitter is sitting on a fastball. If you read around, the “point” of a cutter appears to be to break into an opposite-handed hitter’s barrel, eliciting soft contact. (Cue all the Mariano Rivera videos/gifs you’d like.) I wanted to take a closer look at some examples of how this could be successful in the major leagues as well as just the value of a cutter against right-handed batters from lefties from an analytical perspective, so of course I pinged Ivan for some help.

---

So, let me start out by saying this: when Eric asked me about this, it sent me down a “hey a baby is sleeping on me what am I going to do this week” wormhole about cutters. I now know a lot about cutters. Perhaps more than I wish I knew. The thing is, cutters are weird, for all sorts of reasons. If you think about the basic movement of a cutter, it’s not too different from a slider (just thrown harder):

Now, you don’t often hear of players throwing their sliders to bamboozle opposite-handed hitters. Instead, the conventional wisdom is that a two-pitch pitcher with a fastball and a breaking pitch needs something to beat opposite-handed hitters, like a changeup. Yet, we also have the conventional-wisdom-about-cutters that a cutter can be a platoon-beating pitch, even though it’s basically a slider, which is conventionally not thought of as a platoon-beating pitch. The fear is that a slider would break into an opposite-handed batter’s barrel, yet the idea is that a cutter would break further “in” and get the narrow part of the bat. See, weird!

The other weird part is that even the definition of a cutter can be a bit of a disaster in its own right, which makes talking about cutters difficult. Currently, the Statcast (nee Pitch F/X) data use algorithms about speed and movement to classify pitches; the Pitch Info/Harry Pavlidis data (hosted at Brooks Baseball) start with the Statcast data but make certain revisions and adjustments based on things like reviewing pitcher grips and information about what individual pitchers consider their pitches to be. This might seem like it’s TMI or beside the point, but it’s actually really relevant to analyzing cutters, because you can’t really analyze cutters if you don’t first identify what a cutter is and is not, and that in and of itself proves pretty tricky. But, don’t take my word for it: stop reading this article, and check out this Beyond the Box Score post from Sky Kalkman, back from 2009: https://www.beyondtheboxscore.com/2009/9/14/1029702/every-pitcher-should-throw-a-cutter. No, seriously, read it. Read the comments. I’m not kidding, do it.

You can see this classification challenge very distinctly if you just map the prevalence of cutters according to the (unadjusted) Statcast/MLBAM data versus the (adjusted) Pitch Info data. That’s quite a gap!

Not only is there a gap, but the trends in the two lines have become dissociated in recent history. While they mostly moved in lockstep through 2016, the Statcast data show more cutters year-over-year from 2017 onward, while the Pitch Info data are relatively steady. I’m not going to pretend to know exactly what’s going on here, and my preference for anyone making broad claims about cutter usages would be to look at the adjusted Pitch Info data rather than the raw Statcast data,

So, leaving “how many cutters are actually thrown” aside, another reason that cutters are weird is because they’re both super-good, and not thrown that often. Don’t believe me that they’re not “super-good?” Well — consider three bits of evidence. First, go up and read that Sky Kalkman article this time. (Also read the comments.) Second, look at Nathan Eovaldi’s 2018, and Martin Perez’s 2019 so far. Sure, two guys isn’t proof of anything, but those are some pretty stark differences that follow an easy story of “guy gets cutter, guy gets good.” You can find a lot more. Third, well, data time!

There really could be just an entire analysis based on these results, because they’re so odd, like cutters themselves. The main thing to know is that the cutter is a strictly better pitch in most cases, i.e., the results are just better no matter how you slice it. Across the last four-plus years, the cutter has:

• Been better for lefties than not-a-cutter, though mostly in terms of strikeouts and walks rather than mitigating contact; and
• Been much better for righties than not-a-cutter, and really actually enhanced the ability of RHPs to stifle opposing right-handed batters.

Compare this to just 2018, where, while the cutter is still generally strictly better, it’s actually lost its advantage when thrown by righties, mostly because it’s lost whatever platoon-disadvantage-defying mojo it may have had earlier. Possible reasons for this might be simple dilution, aka the “low-hanging fruit” explanation, i.e., more players add cutters, but they aren’t good cutters, hence the results are comparatively worse. This is just my hypothesis, but it seems possible — what’s surprising is that it appears that this only appears to apply to righties, as southpaws are seeing more cutter gains.

Perhaps the more interesting thing from these tables, however, is that there’s not much evidence for cutters being some kind of magic platoon-beating pitch, at least not in aggregate. In the first table, lefties enjoy a platoon split of 0.027 wOBA points overall, and 0.032 on contact. On the cutter, it’s 0.030 and 0.031, respectively — that is, the cutter actually doesn’t seem to do much against righties that the lefty pitchers aren’t already managing otherwise. There’s perhaps a little more evidence when you look solely at 2018 data, but even so, we don’t see any specific targeted effects in the broad sample. Where we actually see more of an effect on the cutter is on same-handed batters, especially for righties. The one potentially interesting blip is the drop from a .319 wOBA allowed by lefties to righties in general in 2018 compared to a .301 on the cutter, but this isn’t as substantial in the broader sample (first table). Anyway, the results are mixed — there doesn’t seem to be this huge obvious story about cutters being a panacea for defeating the platoon disadvantage, at least not using the unadjusted Statcast data.

But, a pitcher is not just the sum of his pitches. Pitchers have options — they can use one pitch to set up another, or to shore up their weaknesses. Perhaps looking at results on the cutters themselves isn’t the right way to go about it; maybe we should look at pitchers who throw cutters and see what their platoon experiences are instead.

Unfortunately, pitch mix changes, and platoon splits themselves are prone to sample size issues, just like in-season stats themselves. To that end, I took a pretty simplified approach — I’d be overjoyed if someone wanted to extend this, but I’ve already made Eric’s article way too long at this point so I’m trying not to go overboard. In 2018, there were 56 starting pitchers (yes, only 56) qualified for the ERA title. Of these, 17 were southpaws. I sorted the 17 into two groups: a group of seven who threw a substantial number of cutters (Tyler Anderson, David Price, Kyle Freeland, Jon Lester, Marco Gonzales, Cole Hamels, Dallas Keuchel) and a group of ten who did not (Patrick Corbin, Blake Snell, Andrew Heaney, J.A. Happ, Jose Quintana, Gio Gonzalez, Matthew Boyd, Sean Newcomb, Derek Holland, Clayton Kershaw).

The cutter group collectively allowed a .311 wOBA and an FIP/xFIP of 4.03. Against righties, these numbers budged (or didn’t) to .311, 4.06, and 4.08, respectively.

The non-cutter group collectively allowed a .295 wOBA, 3.75 FIP, and 3.81 xFIP. (They were collectively better than the cutter group!) But, against righties, these numbers increased to .303, 3.93, and 3.96. Still collectively better than the cutter group, but a much, much bigger jump.

If you break it down into players, you get something like this, when comparing platoon splits against league average:

In the cutter group, it looks like four of the southpaws have a strong case for reverse splits being exhibited, at least in 2018: Anderson, Lester, Gonzales, and Price. Meanwhile, Hamels, Keuchel, and Freeland appear to have more traditional splits — however, Hamels is a bit weird in this regard with a less-than-expected xFIP split. Is having four of seven cutter-throwing lefties with reverse splits evidence of something? I’m not sure.

By comparison, in the non-cutter group, three of ten exhibited reverse splits to a large extent: Kershaw, Corbin, and Newcomb. The difference between four of seven (57 percent) in one tiny group and three of ten (30 percent) in another tiny group may or may not be suggestive. On the similarly “potentially suggestive” front, we have the fact that six members of the non-cutter group had some pretty terrible platoon splits across the board. (Derek Holland, the remaining tenth guy, is just weird.)

So, does any of this lead me to a strong conclusion with regards to Hayden Deal? Not really. It does seem like there’s something to the idea that a lefty armed with a cutter could neutralize opposite-handed batters, but it’s hardly a fait accompli, as Kyle Freeland threw a ton of cutters last year and still had traditional platoon splits without handling righties particularly well. Similarly, there could be other reasons too, as Kershaw, Corbin, and Newcomb’s 2018 experience shows. Given that a curveball isn’t a very platoon-disadvantaged pitch if it moves in a 12-6 motion and that just happens to be something those guys throw... that’s not really surprising. In addition, we saw from the pitch-specific analysis above that just throwing the cutter in and of itself isn’t really what sets up resistance to platoon splits. Rather, it’s having the cutter as part of one’s arsenal that probably matters more than the results on the cutter itself. To me, that mostly suggests that yes, throwing a cutter can help Deal deal with right-handed batters... but his ultimate success against them is going to depend not just on his cutter but how he mixes it with his other pitches to keep them off balance.

In short, I’m kind of afraid I’ve wasted everyone’s time, but that’s probably, again, because cutters are weird. But so is baseball, so I guess it makes sense. Back to you, Eric.

---

Ivan, I want you to waste my time all the time. You are a scholar and a gentleman. (No, I’m just an internet schmuck.)

So back to the original question: what should we make of Hayden Deal and his cutter? The short answer is that it is too early to tell. Aside from all of the analysis above that Ivan gave that showed that a cutter can be a platoon-split buster but is not always so, Deal is 24 years old and in High-A. To draw any reasonable conclusions, one would want to see him against some more advanced hitters (in particular righties) to see if his cutter is good enough against those guys. Given how well he has been pitching for Florida, we expect him to get promoted soon and we will have some better answers to the scouting-related questions then. There absolutely is a difference between a good cutter and a bad cutter especially when it comes to keeping righties under control and Deal’s ability to maintain his feel for the pitch will dictate how well he performs (and his overall role) going forward.

However, don’t underestimate a guy like Deal and his ability to parlay a really interesting pitch into a successful career. Major league hitters are smart and righties are getting more and more used to seeing changeups from lefties, but are less accustomed to cutters designed to get them out. While it is possible that the most likely destination for Deal down the road is as a reliever that can go multiple innings without significant platoon disadvantages (Ivan’s note: this would be a great opener! Let’s do that!), if he is able to continue to develop the pitch and have it consistent as a plus offering while improving the rest of his arsenal... he gets very interesting very quickly.