The benefits of Carlos Martínez in the bullpen

On Tuesday, MLB.com’s Jenifer Langosch reported that the Cardinals were considering moving Carlos Martínez to the bullpen for 2019.

In fact, pitching coatch Mike Maddux seemed to favor it. Twice when asked about Martínez as a starter, he referenced the performance given by the 27-year-old pitcher out of the pen at the end of last season.

At first, I find it tough to justify a move away from the rotation.

Before his injury-riddled 2018, Martínez had put up three consecutive seasons accruing at least 3.3 fWAR. He broke the 200-inning mark for the first time in 2017. That caliber of pitcher, especially one who’s just entering his prime and may have not yet touched his ceiling, makes sense to just plug into the starting five and leave him.

Still, as Langosch reports, Mike Maddux is really high on him as a reliever. Mike Shildt backs up the possibility. The organization is clearly considering it. One would assume there’s a good reason.

So, I’ll play devil’s advocate.

I can really see four major factors driving the thought of Martínez as a bullpen arm: his previous success in the role, late-game stability, clarity in the rotation and roster flexibility.

History of Success

Thinking back beyond Martínez as a major league starter, one can look to his first two seasons in St. Louis as a force from the pen.

The 2014 version of Carlos Martínez was more versatile than we in the online baseball world have deemed new Cardinal Andrew Miller to be. Martínez made 57 appearances, seven of which were starts. He threw 32.1 innings in those starts, with 57 coming in relief.

Digging further, his appearances weren’t even consistent in length. Martínez would throw two innings one night, then come in for one batter the next.

All that to say, his 2014 season was wildly inconsistent in terms of use. He was still able to accrue 1.3 fWAR while throwing nearly 90 innings in a true hybrid role.

I think that role would strongly resemble what Martínez would do if he were to move to the pen this season.

Even in 2018, Martínez was better at stifling bats when coming from the bullpen:

Smaller sample, as one would expect when comparing these two, but opposing batters saw a major drop in production at the plate when facing reliever Martínez compared to starter Martínez. His ability to suppress runs was much better as a result, even independent of fielding.

But, just one split isn’t going to make this point. Martínez was also much better when the pressure was on. Which means...

Late-Game Stability

Let’s look at the splits for Martínez across high- and low-leverage situations, according to FanGraphs:

Martínez’s peripherals are so much better in those pressure spots.

We know we can’t truly define “clutch,” and that because a player was clutch one season doesn’t mean they will be the next. But across Martínez’s career, he’s been better at limiting plate production in the big moments. His K-BB% goes up by nearly five, and batter wOBA doesn’t break the .200 mark.

Now if we just look at ERA, it’s pretty abysmal. High-leverage situations are, by design, going to include more opportunities to give up runs. FIP tells a different story.

Let’s break it down even further and look at those high-leverage spots as a starter and as a reliever:

Again, small samples. But this breakdown shows just how dominant Martínez was in relief when the chips were down. Opposing batters posted a sub-.100 wOBA. Both his ERA and FIP were under 2.00.

There’s no guaranteeing that translating to this season, but if Martínez were to even come close to that level of performance in tough late-game spots, especially with his ability to make longer appearances, the bullpen would no longer be as much of a stressor.

Mix Martínez in with Jordan Hicks, Andrew Miller and possibly Alex Reyes and the relief group is pretty imposing.

Clarity in the Rotation

A huge focus leading up to the season has been the wealth of pitchers at the Cardinals’ disposal—specifically, pitchers who can make it as a starter.

As of now, the rotation projects to include Martínez, Miles Mikolas, Jack Flaherty, Michael Wacha and Adam Wainwright.

Still, there are several pitchers capable of starting who may either be relegated to a bullpen role or return to Memphis. Guys like Daniel Ponce de Leon, John Gant and Austin Gomber. Dakota Hudson had been stretched out as a starter before coming up in relief for the Cardinals in 2018, throwing more than 130 innings both of the past two seasons.

Ryan Helsley is another young starter who could make his way into the conversation. If Alex Reyes recovers well, he could move from bullpen talks to the rotation.

The point being that Martínez can offer stability in the bullpen—and insurance in the form of long relief appearances—that could allow for some of these fringe names to work their way into the rotation and provide meaningful innings.

Roster Flexibility

Another note from Langosch’s reporting is that the Cardinals may only carry 12 pitchers this season, instead of their usual 13. Martínez in the bullpen, potentially in a hybrid role, lessens the stress of having one less pitcher due to his ability to go deep into appearances.

As many pitchers as there are competing for roster spots, there are position players who deserve to be on a major league roster who may start the year in Memphis if the Cards carried an eight-man bullpen.

A versatile fireman a la Martínez may afford someone like Tyler O’Neill (or more realistically and sadly, Yairo Muñoz) the chance to make the 25-man roster when they wouldn’t have otherwise.

Final Thoughts

I’m still not sold on the idea. Martínez has been a very valuable starter and it’s hard to give that production away. But the thought of him coming out of the bullpen has its merits and, if something were to force him into that role, it wouldn’t be the end of the world.