Mountcastle appears headed to concussion injured list

Out of the lineup tonight, Orioles rookie Ryan Mountcastle is moving toward an exit from the active roster.

The Orioles are expected to place Mountcastle on the seven-day concussion injured list after he absorbed Wander Franco's hard tag on the side of the head last night while attempting to steal second base in the first inning.

Mountcastle came out of the game in the top of the third, with Maikel Franco replacing him at first base. He underwent a concussion evaluation and the club has been monitoring him.

"Still has some concussion symptoms, so he's still in the protocol," said manager Brandon Hyde. "I think it's trending toward the potential of an IL there, unfortunately, but we're going to proceed with caution with it and he's still getting checked out a little bit today. But probably heading that way."

Triple-A Norfolk first baseman Tyler Nevin is on the 40-man roster and an option at first base, though he's batting .226/.298/.402 in 71 games. He has 10 doubles, 12 home runs and 35 RBIs in 295 plate appearances.

Kelvin Gutiérrez has made nine starts and 14 appearances at first base in the minors and three starts in the Arizona Fall League.

Trey Mancini is starting at first base tonight.

The bullpen shakeup resumed today with Isaac Mattson replacing Conner Greene, who was designated for assignment.

"He's been up here a couple times, had a few innings," Hyde said. "You see a good arm, it's just about command, and commanding the ball in Triple-A is different than commanding the ball in the big leagues, especially against American League East lineups. He's got the arm for it. He's just got to see if he can have enough fastball command and secondary stuff to get big league hitters out."

Hyde is operating without relievers Tyler Wells, Tanner Scott and Hunter Harvey, who could return as a group by the middle of the month. Wells threw a bullpen session earlier today.

"That will be huge, there's no doubt," Hyde said. "We've been struggling out of the bullpen. There's no doubt about it. Tyler was really the one I relied on the most to throw strikes, so I've used him in all different sorts (of situations). Then before he got hurt he was kind of pitching toward the end of the game, so it would be nice to get him back.

"Tanner's had some good moments this year where he's come in and punched out guys in big spots, and he's an electric arm. I'd like to see Hunter Harvey get healthy and have him finish the season strong to see what we have there, as well."

Hyde estimated Harvey's return "if all goes well" in the Aug. 15-20 range.

Marcos Diplán made his major league debut last night and retired all five batters faced with three strikeouts. He could earn some high-leverage opportunities based as much on need as production.

Someone has to do it.

"We don't have a ton of options, so he's probably going to be, at some point, just like Greene was last night, where we need to try to fill four innings," Hyde said. "That day in New York when Matt (Harvey) came out with the knee, we had to fill five innings. 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 the other guys an opportunity. You hope that they take it and run with it.

"Diplán, I'd rather a guy not make his debut when we're up a couple runs or when it's close, so I thought that was a good night for him to make his debut, down four, lower pressure. Now, the game is way different when you're down four or up four. Entirely different. And the game is different in the ninth inning than it is in the eighth inning.

"We're trying guys out, we're seeing what they can do."

Dusten Knight already made his debut. What if he earns a save in the majors and wants to perform his trademark backflip in front of the mound?

"I have not talked to him about the flip, no," Hyde said, laughing. "But anybody that's pitched in all the places that he's pitched and independent ball, I think if he's going to come off the mound excited if he gets a save, good for him.

"I'm not sure he's going to do a flip. I've never seen that before."