An Overview of the Cardinals Left-Handed Bullpen Options

Baseball is back! And with that, our long baseball-less nightmare is over. This is the time when long toss videos and routine infield practice excite me because it’s great to see baseball being played after having spent all offseason talking about it.

Beyond the videos of players, the start of Spring Training also comes with media availability, of course. And that means that some very important people are saying some important things. And one of those things is that there’s a competition among the left--handed relievers in the bullpen.

So, with that in mind, I want to take a look at the St. Louis Cardinals left-handed bullpen options and see if we can pick out who might make the Opening Day roster. There’s quite a few of them, 6 (or 7) by my count, and there’s not a whole lot of separation between them, which means that we should all be ready for a close competition to claim 2 spots. And I don’t think there’s anyone who has a real upper hand on anyone else.

To emphasize my point, I’ve compiled the stuff+, location+, and pitching+ of every left-handed reliever on the 40-man who pitched in the majors in 2022.

And, before we begin looking at each option, I just want to clear up one other thing. No one is out of options so I won’t be using that as a consideration.

So, with that that, let’s first dive into the left-handed reliever with the best chance of making the roster.

Zack Thompson

I know I said a few sentences ago that there’s no one with a real upper hand on the competition but that’s not exactly true when it comes to Zack Thompson because he probably does have the upper hand after he ended the 2022 season with a 2.08 ERA and a 3.89 FIP. Thompson was quite simply the best left-handed reliever down the stretch last year and it’s hard to send him back to Memphis after that. But I do think it’s possible and that’s because the Cardinals may want to keep developing him as a starter.

This is purely speculation on my part but Zack Thompson is a former 1st round pick who was developed as a starter and only moved to the bullpen after reaching the major leagues last year. And with plenty of open rotation jobs in 2024, moving Thompson back into the Memphis rotation could make him a viable candidate for one of those roles. And if that happens, there’s plenty of left-handed relief options for 2023.

This is a crucial decision for the Cardinals because I do think a full year in the bullpen this season means that he’ll be a reliever long term. It’s hard to escape the bullpen once you enter it, but it’s even harder to escape it once you’ve been in it for two years.

And the other issue is that Thompson has primarily been a two-pitch pitcher at the major league level. He does throw a changeup and a cutter/slider, but 85% of his pitches last season were either four-seam fastballs or curveballs. To be a starter, he needs a deeper arsenal, but if he won’t expand his arsenal as a reliever then he’s not going to be a starter. And maybe he will expand it this year. He was a rookie last year after all, so it would make sense for him to focus on throwing the 2 pitches he trusts the most.

Before I ramble on anymore about a pitcher I’ve already written about recently, let me just move on by saying that if the Cardinals want him as a starter then his roster spot is in jeopardy. If they’re fine with him as a reliever long term then he’ll make the Opening Day roster. It’s that simple for me.

Genesis Cabrera

While I have Zack Thompson one step above everyone else, the rest of the pack is pretty close together. Interestingly, though, Genesis Cabrera leads all options (including Zack Thompson) in Stuff+ and Pitching+ despite his 5.62 FIP and 16.5% strikeout rate last year.

Every single name that we’ll talk about in this article had a better 2022 season that Genesis Cabrera. Yet Cabrera still ranks above everyone else in these metrics. And we’ve all seen what Genesis Cabrera can look like when he’s at his best. If I were convinced that Cabrera would pitch at his best in 2023, this article wouldn’t even exist. Cabrera would be the clear number 1 with Thompson rounding out the top 2. But since Cabrera floundered last year and there’s an open competition, I now feel the need to write this article.

Part of Cabrera’s struggles last year can probably be attributed to home run randomness. The league average HR/FB% is roughly 10%, meaning that around 10% of all fly balls leave the yard. In Cabrera’s breakout 2021 season, his HR/FB% was a measly 4.5%. That means he was either really good at suppressing home runs or just really lucky. And I would say we got our answer in 2022 but the rate rose to 16.7%, which poses the same question in the opposite direction. Is Genesis Cabrera really bad at suppressing home runs or just really unlucky?

And, honestly, who knows? Relievers are weird and it’s really tough to say whether someone deserves to give up the rate of home runs that he does or not.

What I will say is that Cabrera’s fastball regressed last year and that likely contributed to his struggles. The pitch averaged ‘just’ 96.1 mph after cloocking 98 routinely (97.9 mph on average) in 2022 while losing over an inch of rise. Still, though, the pitch had above average velocity and rise and probably should have played better than it did.

Another problem is that he started throwing it lower in the zone after it thrived at the top of the zone last year. Below is the pitch’s heat map from 2021.

And now, here’s the pitch’s heat map in 2022.

After the diminished velocity and lower location, Cabrera went from surrendering a .289 wOBA against the pitch to allowing a whopping .378 wOBA against the pitch. That’s a huge change. His sinker saw similar results after a similar downturn in pitch characteristics.

Yet, maybe there’s hope for Cabrera this year. After he was sent to Memphis last year, he cited a leg injury that limited what he could do on the mound.

It’s easy to be skeptical when a player cites an injury after he struggles and gets sent down but I don’t doubt that Cabrera was hurt nor do I doubt that the injury limited him.

Here’s why:

The left-hander was placed on the injured list on June 25th for an unspecified reason. At that point in the season, he had pitched his way to a 2.27 ERA in 31.2 innings with 26 Ks compared to 12 BBs. After that IL stint, he had a 10.38 ERA in 12 innings with more walks (8) than strikeouts (6).

Clearly something changed and I don’t think Cabrera just lost it. Take a look at his pitch velocities by month for further proof.

March - 94.86

April - 95.88

May - 96.62

June - 97.04

July - 95.92

August - 95.27

His early season velocities are a bit concerning but I’m willing to chalk that up to his arm getting hot with the weather. And I’m willing to do that because it follow the exact same trend from last year. In March of 2021 (keep in mind that March is still Spring Training), Cabrera was throwing 95.33 mph. That velocity increased every month until June when he was hitting 98.15 mph. The difference is that he maintained his velocity the rest of the year in 2021 whereas he didn’t in 2022.

So, the bottom line is that I’m willing to chalk Cabrera’s struggles up to a leg injury and trust that he’ll be back to being potentially the best lefty in the ‘pen in 2023. Spring Training will be important for Cabrera and he will need to show that he’s back, but, right now, on paper, he would be one of my choices to make the roster.

Anthony Misiewicz

So, I have now penciled in 2 lefty relievers, but they are by no means guaranteed to make the roster. That’s the point of a competition. In fact, there’s a world in which Thompson goes back to Memphis to start and Cabrera doesn’t prove that he’s back and now we still need to find 2 lefty relievers. That world likely doesn’t exist but it’s certainly possible, which is why I’ll continue my analysis with Anthony Misiewicz.

At first glance, Misiewicz is the kind of ho-hum boring reliever that a lot of teams bring in every year to provide depth. Sure, it’s nice that he’s a lefty but he’s 28 years old with a fastball that sits 93 in 1 innings bursts. Doesn’t sound too exciting does it?

But I promise you there’s more to him. I won’t guarantee his success but I will guarantee that he’s more exciting that the average guy a team gets for the ever mysterious “cash considerations”.

For starters, Misiewicz is a primary cutter pitcher and that’s uncommon. It’s not a super intriguing cutter as it doesn’t get a ton of cut but has had fine results and even really good results (.203 wOBA) in a small sample size last year (173 pitches).

This is a pitch that can improve, though. Generally the best cutters (at least by stuff+) are thrown hard with a with >0 inches of cut. According to Baseball Savant, Misiewicz got 0.1 inches of cut on his cut fastball in 2022, which is fine. However, there’s potential for more as the pitch does have good spin and it actually had a solid 3 inches of cutting action in 2020.

Here’s what the pitch looked like in 2020:

And here’s the 2022 version:

You can see the difference between the two pitches as one cuts more than the other but I also want you to notice how they are both thrown in the same velocity range and the pitch that broke more actually had more velocity too (90 mph in 2020, 88.9 mph in 2022). But really, the only difference between the pitch in 2020 and in 2022 is active spin.

For those of you who don’t know, active spin is essentially the percentage of spin on a pitch that contributes to movement. In 2020, Misiewicz’s cutter had 50% active spin. In 2021, that number dropped to 36% and in 2022, it was at 38%. Cutters generally have lower spin efficiency and 45-65% is a pretty good range to live in so I would love to see Misiewicz get back to his 2020 cutter.

He’s already a fine pitcher but as a primary cutter thrower, any improvements to his cutter would obviously make a big difference. If Misiewicz can get less gyro spin and more active spin, his cutter, which is already fine, could add sweep and turn into a true weapon.

I also want to mention his slider, which he literally never throws (4 times in 2022 according to Baseball Savant and 9 times according to Brooks Baseball), but looks flat out nasty.

Why he doesn’t throw that pitch, I have no idea. Maybe it looks too similar to his curveball as they have almost the exact same amount of sweep. Maybe it’s a comfort thing. Maybe it’s something else. But that pitch is filthy and I would love to see him throw it more. It’s also his highest grades pitch by stuff+ (take that with a huge grain of salt because of the sample size) at 132.

The rest of his arsenal is fine. He likes to throw a 93 mph fastball up in the zone to help set up his high-spin curveball but neither pitch is too exciting. For the sake of brevity I’m not going to go in depth on them because I really think it’s the cutter and slider that could make the biggest difference for him with a few tweaks.

I wouldn’t be shocked to see Misiewicz break camp with the Cardinals and I actually really like his acquisition, especially since the Cardinals gave up pretty much nothing in return.

Packy Naughton

Our discussion of lefty relievers brings us to Packy Naughton who deserves to be commended for his work last year and for the fact that he made the Wild Card roster.

His 4.78 ERA is perhaps a little inflated considering his 3.14 FIP and a .364 BABIP seems to be the prime suspect for that. What Naughton has working in his favor is outstanding control (ability to throw strikes) but also really good command (ability to hit spots with precision). That was most evident with his changeup which has a really tight concentration in that low, arm-side corner.

And it’s this pitch which only landed in the zone 35.5% of the time but generated an insane 50% chase rate. That’s simply unbelievable. It’s pretty much a righty only weapon but his ability to deceive hitters makes it an effective pitch with it’s .247 xwOBA overshadowed by a .301 wOBA.

Naughton’s fastball isn’t much to speak of and his slider got hammered even if it did generate a 33.3% whiff rate. His changeup seems to be his best pitch at this point even though his slider is encouraging and I also think he could benefit from switching the usage on his four-seamer and sinker.

Naughton’s sinker has always had better results and it seems to form a better tunneling trio with his changeup and slider. If he’s going to do that, I would like to see him add some sweep to his slider and make it less vertically oriented but even if he doesn’t, I still think he could benefit from switching fastballs.

The Others

There are two other options but I don’t envision either of them being in the Opening Day bullpen. The first option is JoJo Romero, who was good for a stretch but finished his Cardinals tenure with a 4.58 FIP and 15.8% walk rate. His xFIP was better (3.59) but I have him behind Thompson, Cabrera, Misiewicz, and Naughton. I’m not going to give him the full breakdown he deserves because I’m sure you’re getting tired of reading this article by now.

The final options are starters like Matthew Liberatore and Connor Thomas but I don’t think the Cardinals are going to be too eager to take them out of the rotation when they can continue developing as starters in Memphis. There’s too many left-handed options for these two to be considered since it would sacrifice their development.

So, in order, I would say that Zack Thompson is the likeliest option to make the team with Genesis Cabrera just behind him. But I also like Anthony Misiewicz and Packy Naughton and I think they will provide stiff competition in case Cabrera doesn’t look right and/or Thompson goes back to the Memphis rotation.

Thanks for reading, VEB. Let me know in the comments what you think of the options and have a great Tuesday!