Nationals relief pitcher and candidate to close Blake Treinen loosens up during a spring training workout. (Jonathan Newton/The Washington Post)

Blake Treinen’s gaze falls when someone asks the question, and because he is a candidate to close for the Washington Nationals this year, people are asking, over and over. When they ask, his normally cheerful voice sinks into a defiant murmur, because he has heard people wonder if he is too kind to close before.

“I don’t really care what people say about that,” Treinen said, eyes downward when asked one day recently — a turn to stern that pretty much qualifies as an expletive-riddled tirade for a friendly guy like him. Is he mean enough to be a closer? Probably not, if there is such a requirement, because Treinen falls short of any quota for curmudgeonliness. But is he, therefore, too nice to succeed in a role generally believed to require a little bit of crazy?

“I don’t need to be mean,” Treinen said. “I think of it as the hitters are taking something from me. And I’m not going to let them take something from me, when I can take it just as well.”

The Nationals do not have a closer, but will decide on one, because Manager Dusty Baker does not support the idea of a committee. Three main candidates have emerged to fill the role, but all of them come with questions. Shawn Kelley has the most experience, and the high-strikeout stuff, but might not be durable enough for regular duty. Koda Glover has the stuff and the traditional closer comportment, but he is still young and unproven, and struggled late last season.

Treinen might have the best stuff of any of them, a 98-mph sinker that destroys morale and undoes rallies as well as any single pitch in baseball. But the question everyone asks about Treinen, who tried to beg his way into a tryout at Arkansas and transferred to South Dakota State when he did not get one, is whether he has enough grit to handle the closer’s role.

The premise behind the question, that the best closers come with a little extra competitive fire, does not necessarily withstand scrutiny. The greatest statistical closer ever, Mariano Rivera, built a reputation as a quiet, kind teammate. For every Jonathan Papelbon or Rod Beck, one can find someone like Mark Melancon, reserved but relentless. Successful closers do not always fit the mold assigned to their duties, that of a devil-may-care, ultracompetitive mad man out for ninth-inning blood.

Blake Treinen catches a pop fly during a workout. Last season, Treinen held right-handers to a .225 batting average against and lefties to .221. (David J. Phillip/Associated Press)

Certainly, Treinen does not exude that kind of competitiveness, often found calling teammates to chapel or teasing someone in good fun. But the prevailing perception, that he is somehow too soft for ninth-inning duties, is not based on personality, but on some of his early struggles. During the 2015 season, for example, he struggled against lefties and in key situations, so much so that he was sent down for a few weeks in late July. If a guy with a sinker like that can’t get outs, many within baseball posited, something had to be missing upstairs. For a guy who used the phrase “peeved off” to describe his frustration with those 2015 struggles, that missing something seemed to be the usual dose of competitive edge.

Treinen admits that he didn’t exactly know how to be competitive when he was younger. And as a deeply religious man who often reads scripture at his locker, Treinen simply did not seem the type to suddenly discover killer instinct. But over the years, something his old pitching coordinator in Oakland, Gil Patterson, used to say began to sink in more and more.

“He would point out scripture, and say  ‘remember, there are some serious warriors in the Bible. Don’t let passiveness fool you,’ ” Treinen said. “You can go out there and compete.”

Nationals pitching coordinator Paul Menhart has had similar conversations with Treinen. He said it never made much sense to ask Treinen to be meaner or anything like that — it wasn’t in his nature — and trying to be something one is not rarely yields improvement. Instead, they discussed that Bible analogy, too, particularly the fact that “whatever someone’s particular chore or job was — warrior fighter, carpenter, whatever. They gave it their all.”

“He sees it as, I’m going to do my job to the best of my ability,” Menhart said. “I’m by no means going to be nice about it.”

Treinen also started to realize he could evolve past simplicity. For years, coaches told him to trust his stuff, because it was good enough to get hitters out as long as it was in the strike zone.

“I still do,” Treinen said. “But there’s also a point where you say, ‘How can I get better?’ ”

The obvious answer after the 2015 season was to improve against lefties. Treinen learned to be more aggressive inside, instead of just showing hitters a few pitches there now and then to keep them honest. Last season, Treinen held right-handers to a .225 batting average against. Lefties hit .221.

With splits like those, and the ability to throw multiple innings in a row, Treinen might be better suited to the role Andrew Miller filled with the Indians last year — less closer, more firefighter. That is effectively the role he played last year, when he left 84 percent of his inherited runners on base — 14th-best in baseball, a stat that would seem to counter the argument that he is ill-suited to late-game pressure. But as the Nationals decide on a closer, questions will linger about whether the friendly devout Christian guy with a near-constant smile will be able to handle the pressure of a role like that. For Treinen, there is only one way to answer them.

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