Collin McHugh’s 2021 was more interesting than many think

Kim Klement-USA TODAY Sports

While the Matt Olson trade and subsequent extension grabbed most of the headlines early this week, the Braves also reinforced their bullpen by signing RHP Collin McHugh to a two-year deal. While some commenters on here had been clamoring for a McHugh signing (including yours truly), other non-Braves writers took a small dive into McHugh’s profile after his signing was announced and pointed out his solid fit with the team. That being said, while I don’t disagree, I’d argue that those writing about McHugh and his 2021 season have somewhat missed the mark as to why McHugh’s 2021 season was interesting. While I’ve commented about it before, I’ve decided to repackage that comment here as a full-blown FanPost to more easily illustrate those points.

1) A Lowered Arm Slot

The first change is a pretty simple but subtle one: he lowered his arm slot on his pitches across the board. It’s not exactly a major change to McHugh’s profile, and it’s worth noting that he’s been lowering his arm slot in previous years as well. However, 2021 saw his lowest arm slot yet, dropping it to a low 3/4 slot instead of the much-more-vertical slot he demonstrated with the Astros in 2017. If you need a comparison, here’s how it looked all the way back in 2017:


And here’s the arm slot in 2021:


Simple enough on that front.

2) Location Changes To His Cutter

While most of the focus on his pitches goes towards how McHugh altered how much he threw his pitches, I’d argue that they’re not diving deep enough to look at the "why" behind the changes. To do so, we also need to look at how the locations of his pitches changed. In this case, our main focus will be on his slider, four-seam, and cutter.

To start with, let’s look at the heat maps of those pitches in 2019.


If you think nothing looks too out of the ordinary, you’d be right. McHugh primarily relied on a "four-seam up, slider down" approach while also mixing in a cutter and curveball, with the cutter also being thrown for strikes. Some of the cutters are up in the zone, but in general he’s willing to throw it in the middle of the zone as well.

Now, let’s look at 2021. As you might have guessed by this section’s title, we’re most interested in his cutter’s location.


No, I didn’t swap the four-seam and cutter profiles. He’s still throwing a slider in the zone, but while he still throws four-seamers high, his primary "high" pitch isn’t that four-seam but his cutter. While it’s not unheard of, trying a "cutter high, breaking ball low" pairing is certainly much, much rarer. How rare, might you ask? Well, after a lot of digging, I could find only four other examples from 2021, with pitchers who primarily relied on that approach being the Rays’ Ryan Yarbrough, the Nationals’ Will Harris, and free agent Wander Suero, while free agent Kenley Jansen relies more on a similar approach that also incorporates his sinker to his glove side as well. And while he doesn't quite count among the four, it's important to also mention the Rays' Josh Fleming as a similarly unorthodox pitcher, as while he also throws a cutter high, he also throws a lower sinker and changeup as well (in addition to a rare low curveball).

As a speculative aside, I would not be surprised if McHugh’s new cutter location of throwing it like a four-seamer was the product of the Rays suggesting it instead of McHugh deciding on it independently, as both Yarbrough and Fleming utilizing similar ideas does suggest that it’s not just a pure coincidence.

3) McHugh’s Pitch Usage

And now we get to the part that most people have focused on: his pitch usage. In general, quite a few articles have noted that not only has McHugh upped his slider usage, he’s also leaned heavily on his cutter as his second pitch. And while those points are by no means wrong, I’d argue that stopping there doesn’t dive deeply enough. In particular, any analysis of his pitch usage not only needs to divide it up between lefty and righty batters, but also look at how his pitches appear to batters in order to better explain the "why" behind it all.

While traditionally it would make sense to start with how he looks against same-sided batters, in McHugh’s case it needs to start with left-handed batters to get the full picture. As such, we need to look at Baseball Savant’s handy-dandy 3D Pitch Visualizer. As a quick overview, the red line represents four-seamers, the brown line cutters, and the yellow line sliders, with the pink dots representing the points where a batter has to decide whether or not to commit to a swing.


It’s not perfect, but the paths that his cutter and slider take are close enough that it’s not difficult to see how a batter might be fooled by mistaking one pitch for another. While ordinarily using either pitch might not be ideal against a left-handed batter, here there’s enough to suggest that they could play off each other well enough to mitigate any platoon concerns and essentially force batters to guess which pitch is coming. And sure enough, McHugh took advantage of that, throwing almost enough sliders (41.5% usage) as cutters (45.1% usage)

The results suggest that he should keep doing this, as not only did both pitches generate whiff rates in the low 30s, but they also limited hard contact and good results from lefty batters, with a 78.9 MPH average exit velocity and .245 xwOBA for cutters and a 88.9 MPH average exit velocity and .229 xwOBA for sliders. That’s not to say that he forced batters into a pure guessing game, as he tended to use the slider a bit more as an out pitch and the cutter more when he needed strikes. However, for the most part against left-handers he was willing enough to throw either pitch in most situations to the point where batters had to some degree commit to a guess.

Now, let’s look against right handers.


You don’t have to be a genius or too well versed in baseball in general to tell that the paths that his cutter and slider take are blatantly distinguishable. In McHugh’s case, it’s from a combination of the differing paths that the pitches naturally take and the separate release points between his cutter and slider exacerbating that difference. Because of this, his cutter and slider have exactly none of the deception against right-handers that they have against left-handers. So based on that, he should be pretty sunk against righties…right?

The good news is that the answer there is no. Near the end of April last year, Fangraphs’ Carmen Ciardiello had a very fascinating article discussing that upping the usage of a pitch did not really affect its effectiveness against batters. So if McHugh has a pitch that does well against righties, the easy argument to make would be for him to throw that effective pitch more against them in order to compensate, preferably either his cutter or slider. And as it turns out, his slider had generally been that very solid pitch and posted great results against righties. So naturally, McHugh’s solution was just to up his slider’s usage, resulting in him throwing it 59.5% of the time to right-handed batters.

And his results…were still very solid. True, his whiff rate on his slider took a tumble from the low-to-middle 40s to 30.9%, but righty batters continued to have trouble squaring up on the ball, with a small .214 xwOBA and an average exit velocity of 84.1 MPH. To top it off, the pitch especially helped him to limit his hard hit and barrel rates (96th and 98th percentiles, respectively, so while he’d ideally like more swing-and-miss, it’s still very solid production from the pitch. Of course, he was still willing to throw his cutter and four-seam against righty batters, but their usage rates (throwing them 25.9% and 12.7% of the time to rightes, repsectively) are in stark contrast to his heavy slider usage.

Other Remarks and Closing:

Some readers will have probably gotten to this point and noted that I haven’t talked much about his curveball. And while that hasn’t been ignored, it’s also become more of a non-factor, and deservedly so in my opinion. That’s not to say that the pitch itself is bad, and in a vacuum his curve is still perfectly usable and gets above-average movement. However, the main issue with the curveball is that it stands out way too much compared to his cutter, slider, and four-seam, as not only does he generally release the pitch from a higher release point, but the path it takes makes it crystal clear that batters are facing a curveball compared to other pitches and thus eliminates any deception. This is especially apparent by the nosedive in the pitch’s usage, and I would argue at this point that him using it as a "keep the batter honest" pitch to be used sparingly is the best way to handle it.

So, what should we expect from McHugh in 2022? To start, while it’s worth acknowledging McHugh also had some major luck going his way (1.55 ERA/2.12 FIP/3.06 xFIP), he was not only a legitimately solid pitcher, but his changes also show that it wasn’t just a one-year fluke that contributed to his results. Going forward, his 2021 usage by the Rays is likely the ideal way to use him going forward, namely as a pitcher who can be used in a variety of situations ranging from multi-inning relief duty to high-leverage scenarios. While some will point towards his multi-inning capacity and previous starter experience as arguments that he should be considered a starter candidate, his injury history and 2019 questions beyond the first time through the batting order suggest that trying him out as such isn’t a good idea. That being said, if 2021 is any indication (a dangerous argument to use with relievers), McHugh has shown that he can be a deadly weapon out of the bullpen, and for a two-year, $10 million contract with a club option, that’s a very easy signing to make.

All screenshots taken from Baseball Savant, first picture taken from Battery Power Article "Braves sign Collin McHugh to a two-year deal"

This FanPost does not express the views or opinions of Battery Power.