(Al Behrman / AP)

Craig Stammen’s unofficial title remains long reliever, but it is becoming more and more misguided, if not obsolete. He does not behave like one, and Manager Davey Johnson does not treat him like a long reliever.

Monday night, the Nationals trailed by one run in the sixth inning, and the bases were loaded with no outs. The Nationals needed strikeouts or a weak groundballs, a dominating performance. Johnson asked for Stammen. He came into the game, fell behind Jon Jay, 2-0, and proceeded to induce a double play, intentionally walk Pete Kozma and then strike out the pitcher and escape with zero damage.

“Sometimes, you need to back off and let it do what it’s supposed to do and throw it just down the middle,” Stammen said. “That’s kind of what happened last night.”

Here was the only difference between Stammen and a setup man: Stammen stayed out and pitched another inning, throwing a scoreless seventh. In the process, Stammen collected three more swinging strikes, giving him 27 on the season against 42 batters. Opposing hitters have whiffed with 37.3 percent of their swings against Stammen, which ranks eighth in the majors among relievers.

“I don’t even think last year you could call me a long reliever,” Stammen said. “I was just his reliever that went more than one inning.”

This year, though, he has been given even more responsibility. Baseball-Reference.com keeps track of a stat called Leverage Index to measure the importance of a reliever’s appearance, based on the score and the inning. An average leverage is 1.0. Drew Storen leads the Nationals’ bullpen with a 1.62 average index. Next is not closer Rafael Soriano or all-star setup man Tyler Clippard. It is Stammen, the supposed long reliever, at 1.55.

Last season, Stammen received a few chances at a traditional, one-inning setup role when Ryan Mattheus went on the disabled list. “I kind of had to be a setup man, kind of fill both roles,” Stammen said. “With Zach [Duke] doing such a good job kind of handling long situations by himself, it allows Davey, I think, to put me in different kind of situations like” Monday night.

“I like the fact that he can give me more innings,” Johnson said. “He’s better suited for that long man, spot start.”

In this way, Stammen’s durability hurts his perceived value. He remains stuck with the long man title, because he can sponge multiple innings when necessary. With the quality of his swing-and-miss stuff, he may be talented enough for a more high-profile role.

“I think Davey always says this, too,” Stammen said. “If you’re not trying to increase your role, there’s something wrong with you. You’re always trying to have a more influential impact on the team winning or losing games. But I’m also content with what he has me doing, so I can’t do anything about it.  Just do what I do best, no matter what role I’m in.”

By title, Stammen is a long reliever. In practice, he has been used more like a hybrid. He eats innings, but he also strikes out hitters at a high rate and puts up zeros.