In a break from annual tradition, Manager Dave Martinez listed the usual fifth starter candidates — Joe Ross, Erick Fedde, Austin Voth — and then kept going.

“We picked up a kid that we kind of like, too, so four of those guys will be vying,” Martinez said after the Washington Nationals’ first pitchers and catchers workout last week. “Right now it’s wide open, but I’m sure one of these guys is going to step up by the end of spring and we’ll have to make a tough decision.”

The “kid,” it turns out, is 26-year-old Rogelio Armenteros. Martinez avoided his name because he wasn’t quite sure how to say it. The Nationals plucked Armenteros off waivers from the Arizona Diamondbacks in early December. He is still relatively unknown to most in the organization. The basics: He has just five major league appearances (all with the Houston Astros in 2019), missed the 2020 season while recovering from elbow surgery and throws a lot of change-ups.

Like, a lot of change-ups.

But the data on Armenteros is a minuscule sample size. He has 333 pitches in the public record. Realistically, he is a long-shot fifth starter candidate who will swing between the majors and minors as needed. His remaining minor league option made him an attractive waiver add for the Nationals, who subscribe to the cliche that “you can never have too much pitching.” In this case, with this soft-throwing right-hander from Cuba, they are deepening the pool of guys who could start in a pinch.

An unofficial ranking of the starters on the 40-man roster puts Armenteros right outside the fringe:

1. Max Scherzer

2. Stephen Strasburg

3. Patrick Corbin

4. Jon Lester

5-7. Joe Ross, Austin Voth, Erick Fedde

8. Rogelio Armenteros

9. Ben Braymer

10-12. Seth Romero, Steven Fuentes, Joan Adon

This is important because the Nationals had eight pitchers make at least eight starts in 2019. In 2018, 11 pitchers made two or more. Arms are fragile. It’s almost a guarantee that no team can get through a six-month schedule with its desired five-man rotation. There also are added complications — and a louder call for depth — coming off a pandemic-shortened season. And that’s why Armenteros was a quietly smart add for the Nationals.

His remaining options allow them to send Armenteros up and down at their discretion. The above rankings don’t account for one of Ross, Fedde or Voth joining the bullpen as a long man. That doesn’t mean they couldn’t transition back to starting when necessary. But it does nudge Armenteros even closer to his next chance.

The Nationals’ depth was thinned by a couple of moves in the past six months. They turned Kyle McGowin, a former depth starter, into a slider-slinging reliever. They traded Wil Crowe, a depth starter in 2020, to the Pittsburgh Pirates in a deal that netted first baseman Josh Bell. From there, looking beyond Armenteros, they have Braymer, Romero, Fuentes and Adon in the mix.

Braymer is a 26-year-old lefty who impressed in a September outing against the Miami Marlins. Romero, a 24-year-old lefty, is a 2017 first-round pick who debuted last summer to plug a hole in the bullpen. Fuentes and Adon were added to the 40-man roster this offseason, protecting them from being selected in the Rule 5 draft. Both are still a good distance from the show.

Armenteros has slightly more experience than everyone in that group. He beats Braymer in total appearances, five to three, and spent two springs in camp with the Astros. To get there, Armenteros excelled in the hitter-friendly Pacific Coast League. His Class AAA numbers were another selling point for the Nationals.

“He’s got four pitches. He’s got a really good change-up, he’s a strike thrower, throws in the mid-90s,” Martinez said of Armenteros, who made a handful of appearances in the Dominican Republic this winter. “We feel like he’s in that mix. The thing that I like about our spring training is that we have depth. Obviously we’re going to have one fifth starter. The rest of these guys, we have some depth there. So it’s really good to go into a season knowing that if something does happen, we have somebody that can step in and fill the void.”

In those five appearances with Houston — two starts, three in relief — Armenteros’s fastball averaged 91 mph. But it could appear a bit faster to hitters because of how often he throws off-speed pitches.

His 333 major league pitches broke down to about 48 percent fastballs, 29 percent change-ups, 18 percent curves and 5 percent sliders, according to FanGraphs. If that averaged out to a more common sample size, only 10 starters would have thrown a higher rate of change-ups in 2019, according to Statcast. Armenteros’s mix could shift with more confidence in his fastball and curve. Perhaps it should in the long term. But his current approach may endear him to Jim Hickey, the Nationals’ new pitching coach.

“I’m a huge believer in the change-up,” Hickey said in October. “A lot of guys don’t like the change-up because it’s not a sexy pitch. It’s not a huge swing-and-miss pitch for a lot of guys, but there’s a lot of outs in there.”

Hickey added that change-ups are typically easier to throw for a strike than curveballs or sliders. And that, he explained, makes it a critical pitch when a pitcher is behind in a count and hitters may be sitting on their fastball.

To Armenteros’s credit, he has thrown his change-up to any hitter in any situation. His usage is hardly dependent on the count or whether he’s facing a right- or left-handed batter. That’s another reason his fastball could play better than 91 mph suggests.

An odd dynamic with Armenteros is that the Nationals would rather not see him come April. Same goes for whomever loses out among Ross, Fedde and Voth — and Braymer and so on. But every season shows whether a club has pitching depth. At some point, Armenteros’s phone will ring.