BALTIMORE—Thanks to catcher Adley Rutschman, the Orioles took three of four against the Oakland Athletics. Rutschman’s ninth-inning home run rescued the Orioles, who had another disappointing start from Cole Irvin.

Rutschman broke a 7-7 tie in the ninth, hitting a 1-0 pitch off Trevor May for his first game-winning home run and an 8-7 win before an announced crowd of 11,665 at Camden Yards on Thursday.

“Honestly, I just kind of like blacked out. I don’t know,” Rutschman said. “One of those moments that you hit it and you just kind of start running because you don’t know what’s going on. Yeah, glad it went over the fence. You’ve got so much adrenaline going at that point, you don’t really know what’s going on.”

It was Rutschman’s first walkoff as a professional.

“I had an inside-the-park home run in college for a walkoff,” Rutschman said. “I think I had back-to-back nights. One was a line drive to center and the next night was a line drive to center that the guy dived for and missed. I had a walkoff. Sorry, that’s old college. Got to close the yearbook.”

Irvin struggled through four innings against Oakland (3-10), the team that traded him to the Orioles in January. Manager Brandon Hyde pulled him after he allowed six runs in four innings.

“I thought he mixed well today, had a couple of pitches leak over the middle of the plate, some stuff that’s unlucky, but I love the way he goes about his stuff, and he’s going to bounce back,” Rutschman said. “He’s a competitor, and I love working with him.”

After Kyle Gibson worked seven innings on Monday, Grayson Rodriguez and Dean Kremer each got only one out in the fifth, and Irvin didn’t make it that far.

“I’m concerned about our pitching in general right now,” Hyde said. “I feel like we’re going to turn the corner. I feel like we’re going to improve, but we’ve got to get deeper in the game.”

In three starts, Irvin has failed to make it through the fifth and has a 10.66 earned-run average.

“I’m just shooting myself in the foot,” Irvin said. “Bad pitches in bad locations that I know not to go to. It’s just small stuff that I really need to continue to clean up. I’m not happy with how these first three have gone.”

The Orioles (7-6) scored seven runs against Adam Oller and had a 7-4 lead after three.

Irvin got the first two outs in the fourth before loading the bases. A two-run single by Esteury Ruiz cut the lead to 7-6, and Hyde decided to bring in Austin Voth for the fifth.

Brent Rooker, who hit a three-run home run in the third, led off with his third home run in the last two games to tie it at 7. Rooker had three homers and nine RBIs in the last three games.

Ryan O’Hearn, whose contract was purchased before the game, drove in three runs with a two-run single in second and a sacrifice fly in the third. Ryan Mountcastle hit his sixth home run.

After their four-run third inning, the Orioles had just one hit until the eighth. Terrin Vavra and O’Hearn singled, and both moved up on a passed ball. Jorge Mateo struck out, and Vavra was thrown out trying to score on a ly to right by Cedric Mullins.

Notes: Relief pitcher Mychal Givens, who is on the 15-day injured list because of left knee inflammation, was scheduled for a bullpen session in Sarasota. Hyde said Givens is nearing a rehab assignment. … The Orioles visit the Chicago White Sox for three games. Tyler Wells (0-1, 3.27) will facesMike Clevinger (2-0, 3.48) on Friday night.

O’Hearn in, Bemboom out: When the Orioles selected O’Hearn’s contract from Norfolk, they designated catcher Anthony Bemboom for assignment. Bemboom cleared waivers and accepted an assignment to Norfolk.

O’Hearn didn’t make the Orioles after spring training and hit .300 with four home runs and 11 RBIs in nine games at Triple-A Norfolk.

“I felt like I was playing well and if there was a move that was going to happen, I was hoping it was going to be me,” O’Hearn said. “I feel like this is where I belong, and this is obviously where I want to be.”

Bemboom was hitless in two at-bats in two games, but the Orioles weren’t going to keep three catchers for long.

“Love Bemboom. He’s such a pro, team guy, a really good catcher,” Hyde said.

Santander out: Outfielder Anthony Santander was out for the second straight game because of a back injury.

“He’s feeling a lot better today,” Hyde said. “He did treatment all day yesterday and into the game, also. Woke up today feeling better, treatment all morning. He’s going to take swings now and should be available off the bench.”

Santander was not available for Wednesday’s game.

Bullpen changes coming? The Orioles haven’t been able to option pitchers to Norfolk in the season’s first 15 days because pitchers optioned must stay there for 15 days—unless replacing an injured player.

That could mean some changes are coming this weekend since the season started 14 days ago.

“We have some tired arms out there,” Hyde said. “We still have not played our best baseball by any means.”

Defense struggles: Hyde has reiterated that the Orioles’ defense must improve.

“Constant conversations, mental lapses that we haven’t had in the past,” Hyde said. “Our guys are very aware. It’s not that they’re not aware. They’re very, very aware, but for us to be very successful, we’re going to have to play very good defense … They say it, and they know it. I think it’s just a couple of mental lapses early in the season. I would think they’ll start playing better.”

Call for questions: I’ll be answering Orioles questions next week. Please email them to: [email protected]