(AP Photo/Nick Wass)

Sunday afternoon, Manager Matt Williams acknowledged the most glaring issue on the Nationals’ pitching staff, more pressing even than the drop in Taylor Jordan’s velocity and overall efficacy: Finding a way to get more out of Ross Detwiler.

Detwiler is, at worst, the Nationals’ sixth-best pitcher, and they have turned him from a solid starter into their least impactful pitcher. The Nationals moved him from the rotation to the bullpen to give them a versatile, late-inning, left-handed weapon. What they have done instead is give themselves an overqualified mop-up reliever.

Detwiler played a key role in the Nationals’ 4-2 loss Sunday, giving up four hits and a walk as he yielded his first earned runs of the year. But his appearance again came in long relief, the role in which Williams expressly said the Nationals did not intend to use Detwiler.

Detwiler has, by a wide margin, the lowest average leverage index of any member of the Nationals’ opening day bullpen, according to Baseball-Reference’s calculation. What that means: Detwiler has mostly performed early in games or when the game is out of hand.

Detwiler has not pitched in a single situation Baseball-Reference considers “high leverage” – he has three medium-leverage appearances and five low-leverage appearances. Only once has Detwiler entered to protect a lead: when the Nationals led the Mets by six runs. He has been crucial holding the fort in a couple comebacks. But he has mostly been a long man with an inconsistent role.

“It’s difficult with Det, because we try to get him in situations where he can go one-plus,” Williams said Sunday. “It’s been sporadic. So we’ll look to get him in there more often, more regular basis. But with the game today, we’ve got to get him in there, because we need multiple innings. We were in the game at the time. In case we got back, we needed long [relief].”

Detwiler, 28, pitched to a 3.40 ERA in 2012, mostly as a starter. Last year, he punched up roughly the same results before he pitched through a back injury that eventually required season-ending surgery. Detwiler is a solid starter in his prime, and for one month he has filled one of the least consequential spots on the roster. Meanwhile, Jordan has gone 0-3 with a 5.61 ERA.

In theory, the Nationals tapped their surplus of starters for a shutdown, late-inning lefty. In practice, they have given their fifth spot to a prospect who seems unprepared for the job while Detwiler toils in low-leverage situations.

Circumstances have forced Williams’s hand. Early in the season, Nationals starters faltered often and necessitated long relievers. Williams anticipated more consistent starting, and the Nationals entered the year, optimistically, with no dedicated long men other than Craig Stammen. With frequent early innings and a need for innings, Detwiler became one.

“It’s not frustrating,” Williams said. “It’s the way it’s gone. On any given day, you’re going to have to deal with it, whatever it is. It’s easy when your starters go out there and give you seven and you set your bullpen up every day. That’s the plan and that’s what you hope for, but that never happens. It’s been a challenge. But it’s good.”

Detwiler’s role has perhaps affected his performance. He has been quite good, allowing no earned runs in his first seven appearances. But he was wilder than ever. Typically a control pitcher, Detwiler issued eight walks in his first 11 innings.

“The only thing I can think of is, the more he pitches, the better feel he’s got,” Williams said. “Being a former starter, he’s got that routine, certainly. Up until today, he’s walked some guys but he’s done really well. It’s been sporadic, though. If the games go our way, we’ll see if we can get him in there more lefty-lefty matchup, more regular basis.”

Williams’s comments suggest the Nationals are not ready to pull the plug on Jordan’s rotation spot with one start remaining before Doug Fister returns to the disabled list. But you can sense that Williams has identified one problem with the pitching staff. Detwiler is one of his better pitchers, and he needs to find a role that conforms to his ability.