Detroit, which lost for only the fourth time in 13 games, couldn't blame Galarraga, despite the solo homers he served up to Luke Scott and Nolan Reimold.
"We didn't do a very good job of executing tonight, defensively or offensively," Detroit manager Jim Leyland said, "and we paid for it. ... You can't do that and win games."
The Tigers couldn't figure out Orioles rookie David Hernandez early, but Galarraga (3-5) -- coming off an 0-4 May after opening the season 3-0 in his first four starts -- pitched better. It was his best outing since April 26, when he allowed a run on three hits over six innings in his third victory. Since then, Galarraga had given up five or more runs in four of five starts and gotten to the sixth inning only once.
"I thought his slider was better, with the exception of a couple [pitches]," Leyland said. "He threw the ball over the plate better. He gave us a chance to win, but he threw a couple of bad pitches and that's certainly excusable."
Galarraga agreed that his slider has started to come around, but bemoaned two pitches he made that were rocketed over the wall in hitter-friendly Camden Yards. Scott sent a decent sinker to center with two down in the second and Reimold crushed a slider into the left-field seats leading off the fifth, breaking a 1-1 tie for good.
"The first one, I think I made a good pitch," Galarraga said. "The second one, I give credit to [Reimold].
Whether Galarraga saved his spot in the rotation, however, remains to be seen. Right-hander Jeremy Bonderman, who has been out for the entire season with a circulatory problem, is close to returning and is pitching on a rehabilitation assignment with Triple-A Toledo. When he returns, Galarraga could be the odd man out.
When pressed about Galarraga's status, Leyland chased reporters out of his office.
"You guys are worried about Bonderman taking somebody's place," Leyland said. "I'm not going to talk about that. Galarraga pitched a great game, and I'm not getting into all of that."
The Tigers had Hernandez (1-0), who was making his Major League debut, on the ropes in the first and fifth innings. But all they could come away with was one run, a Clete Thomas RBI single that tied it at 1-1 in the fifth.
"You don't quit after the first inning, but it would have been nice to put a little something on [Hernandez]," Leyland lamented. "He was very good."
In the first, Detroit exploited Hernandez's jitters to load the bases with two outs, sandwiching walks to Thomas and Curtis Granderson around a Magglio Ordonez single. But Brandon Inge flew out to left to end the threat.
"Less than two outs, runner in scoring position, I need to get him in," said Miguel Cabrera, who fanned for the inning's second out. "We couldn't hit [Hernandez]."
In the fifth, Jeff Larish led off with a double and Gerald Laird walked before Ramon Santiago -- trying to bunt the runners up -- grounded into a fielder's choice with Larish out at third. Thomas followed with an RBI single up the middle, but Hernandez escaped the jam by getting Placido Polanco to foul out and Ordonez to sky to center.
Hernandez exited with runners on the corners and two outs in the sixth. Reliever Matt Albers loaded the bases by walking Laird, then caught Santiago looking at a third strike to end the inning. Hernandez allowed a run on five hits, walked four and struck out three.
"That's why I'm here -- to drive in runs," said Larish, who fouled out to third for the second out in the sixth. "I've got to come through in those situations. I didn't, and that's frustrating."
Equally maddening to Larish was wasting a good effort by Galarraga. After watching Galarraga struggle for a month, Larish wanted to reward a gutsy effort with a victory. Instead, the Orioles extended their winning streak to a season-high four games.
"He gave up hits, but that's all right if you shut them down," Larish said of Galarraga. "You can look at the hits allowed, but he pitched a good game tonight."
Scott hit a three-run homer off reliever Ryan Perry in the eighth for a 5-1 lead. The game was stopped briefly earlier in the inning after Perry lost a contact lens.