Breaking down the remaining bullpen candidates

WEST PALM BEACH, Fla. - Perhaps the most difficult roster question the Nationals face in the final days of spring training is how to fill in the final vacancies in their bullpen.

It doesn't help that more vacancies have opened up during the course of the spring. Koda Glover's recurring shoulder woes and now Joaquin Benoit's forearm strain have created some openings that might not previously have existed. Not that there's an easy answer to this quandary.

Let's begin with the bullpen slots that are already locked up. We know Sean Doolittle is the closer. We know Ryan Madson and Brandon Kintzler are the setup men.

That's three spots. The fourth almost certainly belongs to Shawn Kelley, who says his elbow is healthy and has a guaranteed, $5.5 million contract. The 32-year-old right-hander is far from a sure thing, no doubt. But he's earned the right to get another shot this season and prove last season was an anomaly.

So that means there are three more vacancies to fill. Two most likely will go to left-handers, one to a right-hander. And somebody from that group has to serve as the de facto long man in the bullpen.

Here are the candidates ...

SAMMY SOLÍS
The 29-year-old lefty has enjoyed the most big league success of anyone in this conversation - when healthy. And that's always been the issue for Solís, who has gone on the disabled list each of the last three seasons, each time with either a shoulder or elbow injury. He has remained healthy this spring, an encouraging sign. And he's pitched well (two runs allowed in eight innings, with 11 strikeouts and one walk). But he's also the only left-hander of the bunch who still has a minor league option. And as we've seen over the years, those often can serve as the deciding factor for end-of-spring roster decisions.

ENNY ROMERO
The 27-year-old lefty has the best stuff in the group, with a fastball that approaches triple digits. He's still trying to develop enough confidence in his slider to make it a trusted second pitch, and he still needs to prove he can throw his fastball for quality strikes (not out of the zone, not over the heart of the plate) on a consistent basis. As was the case last season, Romero is out of options, so he can't be demoted to the minors without risk of losing him via waivers. As much as the Nats would love for him to figure it out, his 10.50 ERA and five walks in six innings this spring haven't helped his cause.

MATT GRACE
The 29-year-old lefty may not have the high ceiling of Solís or Romero, but he also has proven fairly reliable in his 71 big league appearances. He's not really a straight matchup reliever, and he's capable of pitching multiple innings. Grace has given up a whopping 16 hits in 10 2/3 innings this spring, but he's held opponents to only three earned runs. Like Romero, he's out of options, which complicates matters.

TIM COLLINS
An afterthought at the start of camp, the 28-year-old lefty has thrust himself into the conversation with a strong spring that has seen the two-time Tommy John surgery recipient finally healthy again and throwing as hard as ever. Despite his 5-foot-7 frame, Collins has been throwing a 96-97 mph fastball, catching more than a few eyes. He's had big league success with the Royals before his elbow problems cropped up. He's also on a minor league contract and would need to bump someone else off the 40-man roster to wind up in the Nationals bullpen.

TREVOR GOTT
Acquired from the Angels for Yunel Escobar in December 2015, Gott was touted as a promising setup man who could become a stalwart in the Nationals bullpen for years to come. But he's spent far more time at Triple-A Syracuse the last two seasons than Washington and seemingly fell down the organizational depth chart. It's been a good spring for the 25-year-old righty, though. He throws much harder than his small body would suggest, and he's tossed nine scoreless innings in Grapefruit League action. Gott does still have one more option year, so he doesn't have to make the club. But he's made a strong case for himself.

AUSTIN L. ADAMS
Also acquired from the Angels (this time in the Danny Espinosa trade), the right-hander had a nightmarish major league debut last summer and never seemed to fully regain his confidence. He has pitched well this spring, with only one hit allowed in 5 2/3 innings. His command remains an issue, though, as evidenced by his five walks. The Nationals still view him as a big arm who could make a difference long-term. The question is whether they're ready to commit to him yet.

CHRISTOPHER SMITH
One of the few remaining minor league invitees in big league camp, Smith has earned consideration after allowing only one run and three hits in 7 2/3 innings this spring. The 29-year-old right-hander appeared in four games for the Blue Jays last season.