NEW YORK -- Craig Kimbrel was supposed to be the Orioles' closer. After the Trade Deadline, Seranthony Domínguez got his own chance.

But without The Mountain, Félix Bautista, looming at the back of the bullpen, there are still questions there for the O's. This week's series loss to the Mets only magnified them.

Kimbrel's 2024 struggles continued. And Domínguez surrendered two walk-off home runs -- one to Francisco Alvarez in the series opener, and another to Jesse Winker in Wednesday's series finale -- both of which handed Baltimore a 4-3 defeat.

So … now what? Who's the Orioles' closer now?

"I don't have a set closer," manager Brandon Hyde said after the game.

Domínguez had converted saves in three straight outings entering the Mets series. But in New York, where he'd always dominated as a member of the Phillies, he was twice brought into a tie game in the bottom of the ninth inning, and twice surrendered a walk-off blast.

Domínguez is just the fifth pitcher in the last 35 years to allow multiple walk-off home runs in a single series, according to the Elias Sports Bureau.

Pitchers to allow multiple walk-off HR in a series
Last 35 years (via Elias Sports Bureau)

• Seranthony Domínguez, Phillies -- Aug. 19-21, 2024, vs. Mets
• Luke Farrell, Cubs -- May 5-6, 2018, vs. Cardinals
• Brian Fuentes, Rockies -- June 28-29, 2007, vs. Astros
• Octavio Dotel, A's -- May 10-11, 2005, vs. Red Sox
• Mike Fetters, A's -- July 22-23, 1998, vs. Orioles

Things won't get any easier for the Orioles, either. As they jockey with the Yankees for the American League East lead, they head home to face the Astros, then go on the road to play the Dodgers, two first-place teams.

And with the thick of the playoff race ahead of them, they still need to find answers about who can get the most important outs of the game.

"We're searching for outs from whenever the starter comes out until the end of the game," Hyde said. "We're searching for outs."

In Wednesday's game, two of the chief candidates to get those outs, Kimbrel and Domínguez, faltered.

Kimbrel allowed a go-ahead home run to Mark Vientos in the seventh inning. The veteran reliever, who has been taken out of the closer role as he works through his issues, has a 9.53 ERA and five home runs allowed over his last dozen outings going back to July 14.

And after Baltimore rallied to tie the game in the eighth, Domínguez gave up the walk-off to Winker, a hitter he'd struck out in dominant fashion in the series opener.

On Monday, Domínguez blew Winker away with a 98 mph fastball at the top of the strike zone. But on Wednesday, he left that fastball down at Winker's knees, and even at 98.5 mph, Winker drove it out to left-center field to win the game for the Mets.

Domínguez had never allowed a run at Citi Field before this season. But the Mets teed off on him in this series despite his electric stuff.

After Alvarez hit the first walk-off homer on Monday, Domínguez simply said, "I know I can do the job. I'll be better."

But he'll need to figure it out, fast … as will Kimbrel … as will the rest of the Orioles' relievers, as the team enters the stretch of the season where the games are most important.

"We're gonna continue to throw them out there," Hyde said. "Whoever's on the roster. We've got eight guys in our 'pen, and we're trying to find some guys to get hot for us."

In a game like Wednesday's, when the Orioles were scrounging for every hit -- Sean Manaea took a perfect game into the sixth inning against them, before Austin Slater's first home run as an Oriole broke up the no-hit bid and temporarily tied the score -- they don't have any margin for error. That can lead to tough losses if their high-leverage arms aren't perfect.

"It stings," Slater said. "At this point in the season, every game matters."

"With our pitching the way it is right now, we've got to be able to score some runs," Hyde said. "We've got to be able to score some runs, because it's a grind right now on the mound. Until we get through this thing, we've got to be able to help them out, score some runs."