BALTIMORE — The Washington Nationals will welcome Ryan Madson back with open arms when he comes off the disabled list in Atlanta later this week. He is a member of their bullpen’s big troika, a quality, hard-throwing piece they will need healthy to reach a World Series. He makes the bullpen substantially better. Washington will probably add Matt Grace by the end of the weekend, too. He has proven to be serviceable and versatile, able to provide long relief in a pinch. And he’s left-handed, which is a plus for a club that has ridden one of its two left-handers hard (Sammy Solis) and must be careful with the other after two Tommy John surgeries (Tim Collins).

The snag for the Nationals is figuring out whom Madson and Grace are going to replace on the active roster. These decisions are usually simple. But the Nationals’ situation is a little different because their bullpen, after a few additions from the minors, is deeper than it has been all season. Add in contract stipulations and the answers aren’t obvious.

“We still got a few days,” Nationals Manager Dave Martinez said. “Hopefully, nobody gets injured, but we got some big decisions to make. I’m glad these guys are coming back. When those decisions are going to be made, we’ll be ready to make them.”

There are layers to this. The Nationals are already carrying an eight-man relief corps. That’s the max clubs are willing to go nowadays, so adding another reliever isn’t an option. While on the topic, minor league options, and who has any remaining, are a factor. Solis, Wander Suero and Trevor Gott each has at least one left. Collins has two, but because he has five years of service time, he can decline the demotion. Justin Miller and Shawn Kelley are out of options. Brandon Kintzler and Sean Doolittle have options, but they’re not going anywhere.

If a player doesn’t have an option, the team has to designate him for assignment, which means having to trade or place him on waivers within seven days. If a player then goes through waivers unclaimed, he can be released or sent outright to the minors. Players with at least three years of service time, however, can opt for free agency over the assignment. Kelley falls into the latter category. The veteran right-hander is guaranteed $5.5 million this season, but he has pitched infrequently (10 innings) and rarely in high-leverage spots. Recent strong performances, however, could lead to more work in bigger situations.

Miller joins Kelley in that group. Miller, 30, would surely get claimed on waivers because he’s been dominant this season — both in the minors and in his limited time since getting called up over the weekend — and he comes cheap (he’s making a pro-rated portion of his $575,000 deal). Miller added to his case to stick around in the Nationals’ 3-2 win over the Baltimore Orioles on Tuesday night, striking out three in the sixth inning. In three outings, Miller has faced eight batters, struck out five of them and allowed a cheap single. The 28-year-old Collins, meanwhile, has recorded four scoreless innings since getting called up for his first big league stint since 2014. He’s making the pro-rated portion of a $1.25 million salary.

Further, letting a player go diminishes depth, which could hurt the Nationals down the line if injuries surface. Solis, Suero and Gott are the only relievers outside of the Nationals’ big three who could get sent to the minors without the risk of losing them — if a trade isn’t made or a player isn’t put on the disabled list.

Solis is the most proven of the three. Though most of his recent outings have lasted less than an inning, he is pitching more than he ever has in his career. He has appeared in 29 of Washington’s first 54 games, which is already one shy of his career high. Simply warming up takes its toll, and Solis has tested his limits. For a player with his arm injury history, lightening his load would bode well. Adding Grace as a third lefty would help.

The 26-year-old Suero, meanwhile, reached the majors for the first time April 30 and has earned Martinez’s trust quickly. The right-hander has allowed four runs (three earned) in 8 2/3 innings. Gott, 25, has posted a 5.28 ERA in 15 1/3 innings across 17 games, though three of the nine runs he has allowed came in one outing. While he boasts major league stuff, including a fastball in the mid-90s, he hasn’t been able to replicate the sustained success he enjoyed as a rookie with the Angels in 2015, when he tallied a 3.02 ERA in 48 appearances. He was traded to Washington for Yunel Escobar the following offseason.

The Nationals have decisions to make. Madson and Grace are coming and will make the bullpen better. But that’s just one half of the equation. The other half isn’t as clear.

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