SEATTLE -- A bullpen that’s emerged as arguably the Majors’ most surprising has carried the Mariners through the first month and change this season. And though Seattle’s relievers didn’t quite pull off what would’ve represented their most accomplished feat yet, their showing in Monday’s 5-3 loss to the Orioles was still one to hang their hats on.

A six-pitcher shutout of Baltimore was brewing into the eighth inning at T-Mobile Park. But with just three hits and as many runs of support from their bats on the night, the margin for the Mariners’ relievers was thin.

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Having held opponents scoreless all season to that point, Anthony Misiewicz gave up a leadoff walk then surrendered a two-run homer to Cedric Mullins that just barely cleared the right-center-field wall and actually caromed off right fielder Mitch Haniger’s glove on its way out.

Had Haniger hauled that one in, it would’ve been on Mariners highlight reels for years to come. It also would’ve changed the trajectory of a game that was shaping up to be arguably the most impressive performance of the season from the pitching staff, including starters.

“It was a good pitch, just a bad outcome,” Misiewicz said. “I really didn't want to put it in that spot. I wanted to put them off the plate. If you could have one pitch back, I guess that would definitely be the pitch throughout the whole month.”

Charged with the tall task of collectively filling in for No. 1 starter Marco Gonzales, who is expected to miss multiple starts due to a left forearm strain, five Mariners relievers carried the club into the eighth before Baltimore put up a five-spot against Misiewicz and Wyatt Mills, who was making just his second big league appearance.

That snapped a 21-inning scoreless streak by Seattle’s pitching staff that dated back to the fifth inning of Saturday’s loss to the Angels. The five runs raised the Mariners’ bullpen ERA to 2.56, which is still third-best in MLB.

“He was not quite as sharp as he normally is,” Mariners manager Scott Servais said. “We've been using him a lot lately. When you go into a game like this, you try to map it out, and we were in a pretty good spot, but unfortunately we didn't have much cushion to play with.”

The Mullins homer didn’t represent a poor pitch, but rather an impressive piece of hitting. The left-handed-hitting outfielder pulled a cutter on the outer black all the way to the deepest point of the ballpark, and it barely cleared. In fact, according to Statcast, that ball would’ve been a homer in only nine other parks.

“Like I told him as he was walking out of the game, I have no reservations about that pitch at all,” catcher Tom Murphy said. “I do have issues with walks, right? Like, that's way more of an issue than that pitch [for the Mullins homer]. And I think [Misiewicz] would agree on that as well. And he's extremely hard on himself and works really hard. And I hope he sees that as well, because nine times out of 10, that cutter is going to get an out with a lefty. But he knows he doesn't want to walk guys.”

Instead of one on (via a leadoff walk), one out and a 1-0 lead, Misiewicz had to regain himself with a 2-1 deficit and no outs. But his next batter, Austin Hays, found daylight on a grounder that barely passed Kyle Seager along the third-base line that led to a double, representing a tough-luck, would-be second out, possibly even an inning-ending double play.

Mills, who was called up and made his big league debut on Saturday, then came on, allowed one inherited runner to score and gave up a two-run homer to Freddy Galvis that essentially put the game out of reach, even with the help of Haniger’s two-run homer in the bottom of the eighth.

Murphy also went yard with an opposite-field solo shot in the fifth. But those deep flies and a first-inning single by Kyle Lewis represented the lone hits for Seattle’s scuffling offense. Through 30 games, the Mariners are hitting .207/.287/.366 for a 92 wRC+ (league average is 100) and a 26.8 percent strikeout rate, seventh-highest in MLB.

“Not much to talk about offensively,” Servais said. “We had a couple homers. Murph smoked the ball, and Hani got a breaking ball there late in the game. But offensively, we need to be more consistent, and you know, just didn't get much going tonight.”