Oakland let a five-run cushion shrink to 5-4 before Swisher connected against Danys Baez in ninth inning. The solo shot proved pivotal, because the Orioles nearly won it against A's closer Huston Street in the bottom half.
Jay Payton led off Baltimore's ninth with a walk and took third on a double by Corey Patterson. After Chris Gomez struck out, Brian Roberts bounced a single up the middle. Payton scored, but Patterson had to hold at third after initially stepping back toward second base.
"If the ball is fairly close to the pitcher, your first reaction is to freeze or get back," Orioles manager Sam Perlozzo said.
Melvin Mora then inexplicably bunted, and was thrown out at first while Patterson watched from third.
"There wasn't any sign on," Perlozzo said. "I'm sure he felt like the third baseman was deep and that he could get a ball down there and load the bases."
Mora left the clubhouse before talking to reporters.
Although Mora made the second out, the Orioles still runners at second and third. After Nick Markakis received an intentional walk, however, Street earned his fifth save by getting Miguel Tejada to ground out.
"Huston had to come in and face their best hitters, and did the job," Oakland manager Bob Geren said. "It worked out really good for us tonight. It was a big win for us."
Swisher played a big part in it. It was his seventh career two-homer game, and the third time he homered from both sides of the plate. The two home runs doubled his season total.
"The biggest thing for me is feeling comfortable, and I haven't felt comfortable in any situation," Swisher said. "I've been scuffling, and the only thing I know how to do when I'm not feeling good is to keep hitting until something feels right."
Oakland's Dan Haren (2-2) allowed one run, five hits and a walk over seven innings to lower his ERA to an AL-best 1.41. It was the sixth time in seven games that an A's starter yielded one run or less, and the 17th consecutive game in which Oakland starters permitted no more than three runs.
"A big hit by Huff got them right back in the game, (but) what Swisher did there in the ninth, just a quick run for us, was huge," Geren said.
Haren had received a total of five runs of support in his previous four starts, but offense wasn't an issue in this one. Fortunately for Haren and the A's, Baltimore's comeback bid fell short.
Roberts hit his first homer for the Orioles, who had won eight of nine. The sixth-inning drive was Baltimore's lone run against Haren.
Bedard (3-2) retired the first nine batters before giving up five hits and a walk in the fourth. Shannon Stewart led off with a single and Swisher followed with a no-doubt shot to left. Mike Piazza hit a one-out single and Bobby Crosby doubled before Mark Ellis hit a run-scoring grounder.
Bedard gave up five runs and seven hits in 4 2/3 innings. Although he has more than a quarter of Baltimore's 11 wins, the left-hander also has an unsightly 6.11 ERA.
Danny Putnam was recalled from Double-A Midland and made his major league debut, batting ninth and playing right field. He went 1-for-4; his first hit was a fifth-inning single off Bedard.
- Orioles reliever Scott Williamson faced one batter before leaving with tightness in his right triceps tendon.
- Oakland is 7-1 when scoring more than three runs.
- LHP Dallas Braden was called up from Triple-A Sacramento and will start in his major league debut Tuesday.
- Baltimore's Nick Markakis extended his hitting streak to 10 games.
- Oakland has won 12 of its last 14 at Camden Yards.