Minutes after robbing B.J. Surhoff with a runner on in the top of the frame with a sliding, spinning play, Scutaro ripped the first walk-off homer of his big-league career to beat the visiting Baltimore Orioles, 3-0.

Just another thrilling August victory for a team that's made a killing on them for the past four years. Since 2001, the A's are 81-28 in the month; the next best team has been the Cardinals, at 70-42.

"The way things have been going," said A's starter Rich Harden, "you kind of feel like something like that was going to happen."

That something, which earned Scutaro a pounding from a pack of jubilant teammates at home plate, allowed the A's to maintain their half-game lead over the Angels in the American League West.

"They beat me up pretty good," Scutaro said, "but it's a great feeling."

The Orioles went into the game saddled with a season-high eight-game losing streak, and their starting pitcher for the night was a 27-year-old journeyman playing for the ninth organization of his career.

The A's went into the game winners having won eight of their past 10 games, and Harden hadn't lost in 11 starts dating back to June 21.

Pretty good odds for Oakland, right? On the field, it was another matter entirely.

Baltimore's Bruce Chen, whose contract was purchased from Triple-A Ottawa earlier in the day, took a no-hitter into the sixth inning and left the game with a shutout intact after the seventh.

Lefty reliever B.J. Ryan breezed through a perfect eighth and quickly got the first two outs in the ninth, but he gave up a single by Damian Miller and a walk to Bobby Crosby before serving up Scutaro's fifth homer of the year.

"I was just trying to make good contact and see what happens," Scutaro said. "I never go up there thinking about a home run."

But he was thinking about the steady diet of inside fastballs Ryan had served him last week in Baltimore, and when he got another one on a 2-1 count, he punished it.

"I just couldn't make my pitch," Ryan said. "He got ahead of the count, and I tried to make a pitch and got too much of the plate. I just didn't make a good pitch."

That it wasted such a fine night by Chen while extended Baltimore's losing streak made it particularly tough to swallow. The A's didn't hit many balls hard at all against Chen, and the knock that broke up the no-no -- by Eric Chavez -- was a two-out popup that landed in no-man's land behind second base, just in front of hard-charging Orioles center fielder Val Majewski.

"Well, heck yeah, it's tough," Ryan said. "He just pitched seven scoreless, had a no-hitter in the sixth. He came in and did his job, and I didn't. So yeah, it makes it a little tougher."

Harden was awfully tough himself. Only two runners got as far as second base against him, and got better as the night wore on, retiring 11 of the final 12 batters he faced. He allowed four hits and a walk while striking out five before leaving after the eighth.

Now 5-0 with a 2.70 ERA in nine starts since the All-Star break, Harden wasn't at all bummed that his effort was only enough for a no-decision.

"My goal when I go out there is to get deep in the game and give us a chance to win," he said. "I did that, and the team won the game. That's all that really matters."

The win went instead to A's closer Octavio Dotel, who gave up a one-out single to Melvin Mora before getting Miguel Tejada on a fly ball to deep right before Scutaro's sensational play on Surhoff.

In discussing the play, A's manager Ken Macha started to explain the old adage that players who end a half-inning with a great defensive play often lead off the next inning. But then caught himself, realizing that Scutaro was the fifth hitter in the bottom of the ninth.

"He didn't lead off," Macha said. "He finished off."

This story was not subject to the approval of Major League Baseball or its clubs.