BALTIMORE—The Orioles continue to adjust their bullpen. On Saturday they recalled right-handed pitcher Isaac Mattson from Triple-A Norfolk while designating right-hander Conner Greene for assignment.

They also addressed the concussion symptoms for first baseman Ryan Mountcastle, who was removed from Friday night’s game and placed in concussion protocol. Mountcastle could be placed on the seven-day concussion injured list.

“Still has some concussion symptoms,” manager Brandon Hyde said. “Still in the protocol. Still trending toward a potential IL, unfortunately. We’re going to  proceed with caution with it and he’s still getting checked out today, but probably heading that way.”

Mattson was acquired from the Los Angeles Angels in December 2019 with three other right-handers in the trade that sent Dylan Bundy out west. In two games, he has allowed a run on two hits. He struck out one and walked one and was returned to Triple-A Norfolk after the game.

At Norfolk, Mattson is 0-2 with a 9.53 ERA with a save in 14 games. Greene had a 14.73 ERA in three games.

“You’re going to have guys pitch in spots that are going to be challenging at times,” Hyde said. “And maybe they’re not ready for, and maybe they are just because we don’t have a typical veteran bullpen group, so guys are going to get opportunities here, and hopefully they pitch well and stick.”

Marcos Diplán made his major league debut and retired all five batters he faced on Friday night.

“It was nice to see Diplán get an opportunity last night,” Hyde said. “He did a nice job and had a strong ninth inning. Hopefully, we can get more guys like that to be able to get some outs for us.”

Hyde said Diplán could get a chance in a higher-leverage spot.

“We don’t have a ton of options so he probably is going to be [an option] at some point just like Greene was last night when I wanted to try to fill four innings,” Hyde said.

“You can’t pitch the same guys every single night. A few of the guys that I have have struggled as of late, so you try to give other guys opportunities, and you hope that they take it and run with it.”

Hyde likes to have pitchers make their first appearance in a game that isn’t close. The Orioles trailed 10-5 when Diplán entered.

“The game is way different when you’re down four or up four, entirely different,” Hyde said. “The game is different in the ninth inning than it is in the eighth inning. We’re trying guys out to see what they can do.”

Diplán said his major league debut was special.

“One of the best moments of my life,” Diplán said through a translator. “It’s been my dream ever since I started playing. I’m so excited and happy that that came to reality and I felt very proud.”

He said he wasn’t nervous.

“Back home in the Dominican Republic, the fans go crazy,” Diplán said. “They yell so much stuff at you.”

Diplán hopes to get some save chances.

“I would definitely like the opportunity to be in close games,” he said. “I believe you still have to earn those spots. Little by little with more time and opportunities, if I do my job well, I think they might consider me for such opportunities.”

Within the next two weeks, Hyde hopes to get right-handers Hunter Harvey (right lat strain), Tyler Wells (right wrist tendinitis) and left-hander Tanner Scott (left knee sprain) back from the 10-day injured list.

“That would be huge,” Hyde said. “We’ve been struggling in the bullpen, no doubt about it. Tyler was the one I relied on the most to throw strikes. Before he was hurt, he was pitching toward the end of the game, so it would be nice to get him back.

“Tanner’s had some big moments this year where he’s punched out guys in big spots. He has an electric arm. I’d like to see Hunter Harvey get healthy and finish the season strong and see what we have there.”

Left-hander Ryan Hartman, who was on the injured list as part of Covid intake, was removed from the injured list and has returned to the Triple-A Norfolk roster. Hartman was acquired from Houston on waivers on July 30th.

Right-hander Shaun Anderson, who was designated for assignment on Wednesday, was claimed on outright waivers by the San Diego Padres.