To understand how hamstrung for pitching the Orioles have become in recent weeks and to comprehend the swiftness of the collective U-turn they’ve taken on the mound, the most telling visual may have come Saturday in the form of Adam Plutko, head down, circling the grass behind the Nationals Park rubber.

Plutko had just allowed Ryan Zimmerman’s fourth-inning, three-run, go-ahead home run, the deciding blow in a series of big swings that resulted in the Orioles’ 12-9 loss to the Nationals, their 12th defeat in 14 games. The latest came in a seesaw affair; they spotted Bruce Zimmermann an early five-run lead, with manager Brandon Hyde summoning Plutko in the fourth after Zimmermann watched it shaved to one.

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It was an assignment that, a month ago, Hyde expected Plutko to handle with aplomb. Now it’s hard to know what he can reasonably expect, not just from Plutko, but from anyone in his heavily-taxed bullpen, which has seen its collective ERA balloon by more than a full run this month. Plutko is perhaps that unit’s most curious case, given his relative experience and dominant start to the season.

“He had five really good weeks, and these last couple weeks have been tough,” Hyde said. “They are hitting him hard right now. This guy has pitched in the big leagues quite a bit and in the American League. He’s in a tough stretch right now. … He’s just not missing the bat right now.”

Nearly untouchable early in the year, Plutko emerged as Hyde’s most trusted middle-innings option by holding opponents to three runs in his first 15 appearances, a span of 21 1/3 innings. He’s now allowed 10 earned runs over his last three outings: four in an opener appearance May 16, two in high-leverage innings behind John Means on Wednesday, and the game-tying and three go-ahead runs in Saturday’s loss.

All told, O’s relievers have surrendered 28 earned runs in 32 innings over the past calendar week. 

“The opener wasn’t the precursor to things happening,” Plutko said. “I walked the leadoff guy in four or five straight innings before that and they just didn’t score. It was something I was conscious of before the opener outing. What happened with the first [15] outings, compared to now? It’s execution. ... How many balls are in the middle of the box right now? And how many balls [were] in the middle of the box when I was on that good stretch?” 

Elsewhere in his postgame interview, Plutko implored journalists to focus on the positives from Saturday’s defeat, noting how he made Trea Turner “look pretty foolish” during his second inning of work, for one example. And there were highlights in an afternoon in which the O’s offense broke out for nine runs off Jon Lester and five Nats relievers, most notably Ryan Mountcastle’s first career grand slam in the first inning and Anthony Santander’s three-hit effort.

The problem with Plutko’s request is the way Baltimore’s pitching keeps rendering these offensive highlights all moot, on a near-nightly basis for two full weeks. Saturday also marked the worst start of Zimmermann’s career, and had the O’s scrambling to summon at least one fresh arm from Triple-A before Sunday’s series finale. More shakeup could be in order if they decide to swap Zimmermann (5.59 ERA) out of the rotation for another rookie; all told, the O’s staff has now allowed 74 runs over its past nine games. 

Asked late Saturday if he is concerned those struggles might affect morale, Hyde nodded his head. 

“You want your guys to feel good, you want your guys to feel good,” Hyde said. “I do worry about that. It’s been a couple tough years and we’re not winning games the last couple weeks, and that’s not easy. It’s tough to lose in the big leagues. You want guys to feel success.”