As it turns out, the Orioles not only blew a six-run lead on Monday against the Boston Red Sox at Fenway Park, they lost the right side of their infield for what could be an extended period.

Veteran first baseman Derrek Lee, who strained his left oblique in that game, was put on the 15-day disabled list Thursday. Second baseman Brian Roberts, who started Monday's contest with a head-first slide into first base to beat out an infield single, was put on the seven-day concussion disabled list.

Roberts has been experiencing headaches and concussion symptoms following the slide into first base. That raised concern after the 33-year-old second baseman missed the final six games last season with concussion symptoms that lingered well into the offseason.

Roberts would be eligible to come off the seven-day disabled list following Monday's off day. The seven-day disabled list was created before this season to allow injured players, team doctors and athletic trainers more flexibility in addressing head injuries.

"Anytime you're dealing with a concussion and heads and stuff, you're concerned about it," said Orioles manager Buck Showalter. "I was talking to Brian. This isn't anything like the symptoms he was feeling last year. That's good, but you still have those symptoms that we're going to make sure that we have our arms around it before we go forward. We're hoping that it clears up and the doctors feel fine about it, and he's a player on Tuesday."

Lee would be eligible to come off the disabled list June 1. However Showalter, whose club lost shortstop J.J. Hardy for a month with an oblique injury, said it is "iffy" that Lee will be immediately able to come off the disabled list when he's eligible.

"He came in [Wednesday] and talking to him, he felt some improvement and thought that he might be back. But from yesterday to today, it was about the same," Showalter said. "I don't want to lose Derrek. I'd like to have him. He impacts our team in a lot of ways, but taking a chance on this? The medical people think we could potentially take care of it during the DL period, but in my mind, that's iffy for me. We'll see. My experience with these things over the years, there is usually a lot more going on there than you think. I hope not. I think there's some talk about taking some form of an X-ray or something that shows certain inflammations to try and judge how bad it is."

Lee, who was the only Oriole to start the team's first 40 games, had hoped to give it a few more days, but the Orioles decided to make a move.

"I understand the situation that they're in," Lee said. "At the end of the day, you have to do what's best for the team."

Brandon Snyder started at first base in Lee's absence, and Robert Andino started at second base.

2 pitchers down, 2 position players up

The Orioles continued to shake up their roster as they demoted pitchers Troy Patton and Chris Jakubauskas, who had just been recalled earlier in the day, after the game.

They'll promote outfielder Nolan Reimold and second baseman Ryan Adams from Triple-A Norfolk to fill their spots in time for tonight's series opener against the Washington Nationals.

Reimold is hitting .237 with six homers and 22 RBIs in 39 games for the Tides. He has played in 143 games over the previous two seasons with the Orioles, batting .262 with 18 homers and 59 RBIs.

With Luke Scott expected to play some first base with Lee on the disabled list, Reimold could platoon with Felix Pie in left field.

Adams, a 24-year-old second baseman, was hitting .303 with two homers and eight RBIs in 38 games for Norfolk. He still has yet to make his major league debut. With Roberts and Cesar Izturis on the disabled list, the Orioles were down to two middle infielders before Adams' promotion.

Jakubauskas and Patton had been called up to bolster a bullpen that was needed to log eight innings Wednesday.

In the Orioles' 13-2 loss, Jakubauskas pitched 31/3 innings, allowing three earned runs on seven hits and two walks. Patton allowed two runs on two hits and a walk while striking out three over 21/3 innings.

Gonzalez apologizes, says he'd fight suspension

Michael Gonzalez tried to get in touch with Chris Dickerson, who the Orioles reliever hit in the helmet with an errant fastball in the 15th inning Wednesday night, but the Yankees outfielder was at a local hospital having a CT scan performed.

Gonzalez spotted Dickerson behind the batting cage before Thursday's game, and approached him to see how he was doing and make sure the Yankee understood that there was no intent behind the pitch.

"I just wanted to make sure that he was OK," said Gonzalez, who hugged Dickerson. "Obviously, it wasn't my intention. I wasn't trying to hit the guy. I felt a much better peace of mind when I got to talk to him. He understood the whole situation. He said that he knew I wasn't trying to hit him. That means the world to me. When I saw him out there walking around, I was very happy with it."

Gonzalez was immediately ejected by home plate umpire Dan Bellino. He isn't sure if he'll face disciplinary action, but he said that he'd appeal a suspension if he gets one.

"I'm definitely going to fight it," he said. "That was uncalled for. Anybody watching that game is going to know that there was no intention there."

Around the horn

After Matt Wieters was behind the plate for 15 innings Wednesday, Showalter started Jake Fox at catcher Thursday. Fox caught Brad Bergesen's complete-game shutout in his previous outing against the Tampa Bay Rays. … Jeremy Guthrie, who was used for one inning of relief Wednesday, had his next start pushed back to Saturday. Jake Arrieta and Chris Tillman will start Friday and Sunday, respectively, against the Nationals. … Left-hander Brian Matusz (strained left intercostal) will make another rehab start on Saturday, this time for Double-A Bowie. … Izturis will have surgery to move the ulnar nerve in his right elbow Tuesday. It will be performed by team orthopedist Dr. John Wilckens. Izturis is expected to miss six to eight weeks. … Starting on Monday, the Orioles will have four off days in a 22-day span, though Showalter said that the club is likely to stick with a five-man rotation. … Showalter said Triple-A Norfolk catcher Craig Tatum (shoulder) is close to coming off the minor league disabled list and returning to game action. … Mike Bordick will represent the Orioles at the first-year player draft on June 6.

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