Harden, Kotsay, Johnson and Bradley are on the DL, fourth outfielder Bobby Kielty was unavailable because of a calf strain, and A's manager Bob Geren didn't want to use his regular starting right fielder, Travis Buck, because Buck's wrists are sore.
So here's the defense that took the field for the bottom of the first inning behind lefty Dallas Braden, who was making his big-league debut: Rookie Danny Putnam, called up from Double-A the day before, in center field for the first time since instructional league; utility infielder Marco Scutaro making his first Major League appearance in left field; and journeyman utility man Todd Walker at first base.
It looked like a Cactus League "B" game in Surprise, Ariz. -- the day after a night game in Phoenix.
"I don't want to say that," second baseman Mark Ellis said. "It wasn't that bad. But after Swish went down, you're kind of thinking, 'Man, what's gonna happen next?"
What happened next is what's been happening all year for the A's. They rode their remarkable starting pitching while doing just enough to win offensively, closing out a mini-sweep with a 4-2 victory.
"I wasn't worried at all," said Braden, a 24-year-old lefty who opened the season at Double-A Midland. "This is the big leagues. Everybody can do everything."
Braden proved that himself as a freshly minted Major League starter, using all of his pitches -- except his screwball, which pitching coach Curt Young said Braden has been asked not to use -- in every imaginable count and situation while holding the host Orioles to one run on three hits and a walk while striking out seven over six innings.
"He definitely wasn't scared," A's catcher Jason Kendall said. "He can throw anything at any time. He threw the snot out of the ball."
And to Braden's delight, his grandmother, Peggy Lindsey of Stockton, Calif., was in the stands to see it.
After the game, Braden explained that while growing up in Stockton, he and his mother shared a dream of him one day pitching in the Majors. After she passed away in high school Braden made a promise to Lindsey.
"I told her, you will see me in the big leagues," Braden said. "I'm glad that came true."
The moment it did, just before Braden took the mound in front of that makeshift defense, he caught his grandmother's eye.
"She just smiled, and I could see her wink."
Everyone listening to Braden recount his big day was smiling, too, as the tatted-up, nipple-pierced rookie ripped off a series of big-league quality lines.
Called up from Triple-A Sacramento on Monday, Braden eased into his impromptu comedy act with his responses to questions about whether he'd felt nervous before or during Tuesday's game.
"For the past two days, I haven't been able to feel anything on my body," he said. "It's hard to pitch on a cloud, but I had to find a way to do it."
Then he went for the kill in explaining how much information about the Orioles was at his disposal as he prepared for the game.
"Up here," he said, "I'm pretty sure that if I asked someone, they'd be able to tell me what Miguel Tejada had for breakfast this morning."
Whatever information Braden used, he used it well. And the A's took advantage of some less-than-brilliant Baltimore defense while scoring all of their runs without the direct benefit of a base hit.
Swisher singled with one out in the first inning and took second on a wild pitch, but while trying to stop after rounding third on a single up the middle by Eric Chavez, he appeared to run his right ankle and crawled back to the base before being helped off the field with what the A's later announced was a strained left hamstring.
"He said it's not that bad," Geren said. "That's what I was hoping to hear."
But, Geren added, "I'd say there's a real good chance Putnam will be in center field Wednesday. We'll see."
Scutaro replaced Swisher and scored on an error by O's third baseman Melvin Mora, whose animated reaction to the gaffe -- he threw his hands up in disgust while walking toward the mound -- allowed Chavez to alertly move take third base, and he scored on Walker's sacrifice fly.
Baltimore cut the lead in half in the second when Aubrey Huff tripled and scored on a groundout, but that groundout started a stretch in which Braden retired 14 of the last 16 batters he faced.
Braden's work extended an Oakland record run of 18 consecutive games in which the starting pitcher has allowed three runs or less. It also marked the 11th time in 20 games that an A's starter has given up one run or less, and that's happened seven times in the past eight games.
"It's fun to catch these guys," Kendall said. "You put the glove down, they hit it."
The A's padded the lead for Braden in the sixth, and again they got some help. With the bases loaded and two out, Jason Kendall hit a routine ground ball to O's second baseman Brian Roberts, who flipped the ball to shortstop Tejada, looking for an inning-ending forceout.
Tejada, however, appeared to have been expecting Roberts to throw to first base, so he was late arriving at second base and beaten to it by Ellis as a run scored.
"I though [Roberts] was going to first, too, because there [were] two strikes on Kendall and I had a huge jump," Ellis said. "That's why I didn't even slide."
Putnam then walked to pick up his first big-league RBI and made it 4-1.
"We should have been in that ballgame better than we were," said Baltimore skipper Sam Perlozzo.
Back-to-back doubles off Jay Witasick to open the bottom of the seventh cut Oakland's lead to two, but Jay Marshall, Justin Duchscherer and Huston Street worked the final 2 1/3 innings -- Street picked up his sixth save in seven chances -- to wrap things up.
So while the injuries continue to mount, the A's continue to win more often than not, leaving Geren, who is to positive what Liberace was to camp, in fine form when discussing everything from the road trip to Scutaro's appearance in the outfield.
"I kept telling Scoot: You're not playing right field," Geren said. "You're playing a deep second base."