BALTIMORE -- Their rookie starter gave up six walks, hit two batters and committed a balk in five innings. They allowed a successful double steal, couldn't once retire the side in order and blew a 3-0 lead.
Melvin Mora and Miguel Tejada hit run-scoring singles in the seventh inning, and the Orioles received another fine performance from the bullpen in their season-high tying third straight victory.
"It's a good feeling we've got in the clubhouse now," said Mora, who had two hits.
Oakland won three of four in Boston coming off the All-Star break, but the Athletics didn't look like a first-place club in Baltimore. They got only five hits, went 0-for-11 with runners in scoring position and permitted two unearned runs.
"That wasn't a very well-played game," Oakland manager Ken Macha said.
Brian Roberts went 2-for-2 with two walks for the Orioles, who went up 5-3 against Kirk Saarloos (3-6) in the seventh.
Nick Markakis and Roberts hit one-out singles before Brandon Fahey bounced into a force play at second. Mora then lined a single to center and Tejada grounded a single up the middle.
"We need those guys to hit like that," Orioles manager Sam Perlozzo said of Mora and Tejada, the Nos. 3 and 4 batters. "They're the meat of our lineup. They've been coming through lately, and that's a good sign."
Kurt Birkins (5-1) worked the seventh, Todd Williams gave up a hit in the eighth and Chris Ray got three outs to earn his 23rd save in 24 chances.
Coming into the game, Orioles relievers had retired 16 straight batters. The run ended when Chris Britton gave up a sixth-inning run, but the A's got only two hits the rest of the way.
Recalled from Triple-A Ottawa on Friday for a second stint with the Orioles, starter Adam Loewen gave up one hit and struck out five in five innings. But the left-hander struggled with his control for much of the night.
He threw 92 pitches, 44 of which were ruled outside the strike zone by plate umpire Tim Tschida.
"It was frustrating at times, but we won," Loewen said.
Oakland starter Jason Windsor allowed three runs and five hits over five innings in his major league debut. He walked three, struck out three and yielded two unearned runs -- by virtue of his own throwing error.
"I felt like I was getting stronger as the game went on," Windsor said. "I will settle down next time. It's a lifelong dream to get here, and now I want to stay a while."
Windsor got his major league career started by walking the first batter he faced, Roberts, who scored on a single by Tejada before Jeff Conine hit into a double play.
Windsor benefited from a double play in the second inning, too, but yielded two unearned runs in the third. With two outs and a runner on third, the rookie fielded a grounder by Tejada and threw the ball far over the head of first baseman Nick Swisher.
"That's just plain stupidity. It didn't slip at all. It was just a bad throw," Windsor said.
Conine followed with an RBI single for a 3-0 lead.
Oakland scored twice in the fourth without a hit, ending the Orioles' run of 26 straight innings without allowing an earned run. Loewen walked the bases loaded and then walked Mark Ellis to force in a run before committing a balk.
Loewen left with a 3-2 lead, but Oakland tied it in the sixth. Jay Payton and Milton Bradley hit singles, and Payton tagged and took third after Markakis made a leaping grab of a liner to right by Bobby Crosby. Payton then scored on the front end of a double steal, breaking for home after Bradley got caught in a rundown.
Actor Tom Hanks led the crowd in spelling out O-R-I-O-L-E-S from his suite during the seventh-inning stretch. Director Ron Howard and comedian Dennis Miller were also in attendance. ... The Orioles played without DH Javy Lopez (sore back) ... Oakland was without CF Mark Kotsay (knee). ... Baltimore LHP Tim Byrdak, who's been on the disabled list since spring training after elbow surgery, allowed one run and two hits Monday in his first rehab assignment, for Single-A Aberdeen against Jamestown. ... The last Oakland starter to win in his debut was Aaron Harang, on May 25, 2002.