OAKLAND -- Jesse Chavez matched a career high with nine strikeouts in six innings, and three relievers pitched scoreless ball to lead the A's past the Giants 5-0 on Monday night for their fifth straight win.
Alberto Callaspo hit a two-run double, and three others drove in a run to power the A's in front of an announced sellout crowd of 36,067 festive fans at O.co Coliseum.
The Coliseum had a colorful sprinkling of green and gold from Oakland revelers mixed with the orange and black of San Francisco supporters for the Bay Bridge Series opener.
Chavez (7-5) allowed four hits and two walks to help extend the A's record to a majors-best 56-33. Fernando Abad, Dan Otero and Ryan Cook shut down San Francisco the final three innings.
Ryan Vogelsong (5-6) lost his third straight start for the Giants, who had just five hits.
The right-hander gave up five hits and three runs in 5¹/³ innings. He struck out four, walked two and hit a pair of batters, leading to Oakland's first two runs.
The banged-up Giants had lost 18 of 23 to fall out of first place in the NL West -- where they once held a 9½-game lead over the Los Angeles Dodgers -- but showed signs of coming out of their slump by winning two in a row at San Diego over the weekend.
Instead, the two-time defending AL West champion A's put together the kind of all-around effort they've had most of the season to swipe the Bay Area headlines from the Giants again this summer.
Oakland started its scoring surge after home plate umpire Paul Nauert ruled Craig Gentry was hit by a pitch on his hand leading off the fifth. Giants manager Bruce Bochy challenged the play, which was upheld after a video review.
Gentry stole second, advanced to third on Coco Crisp's bunt single, and scored on John Jaso's groundout for the A's first run.
Josh Donaldson also was hit by a pitch by Vogelsong on his left hand leading off the sixth. Nauert asked first base umpire Angel Hernandez if Donaldson swung at the pitch, and Hernandez signaled no.
Callaspo came through later in the inning with a two-run double off Juan Gutierrez to extend Oakland's lead to 3-0. Brandon Moss and Donaldson each drove in a run off Gutierrez in the seventh after Giants shortstop Brandon Crawford committed two throwing errors.
NOTES: Chavez also struck out nine twice earlier this season. ... Gentry is 16 for 16 on stolen-base attempts. ... Giants 3B Pablo Sandoval, who left Saturday's game because of a bruised left elbow after he was hit while swinging at a pitch, sat out for the second straight game. ... A's RF Josh Reddick took batting practice and fielded fly balls for the first time since re-aggravating his right knee injury June 28 at Miami. ... Giants 2B Marco Scutaro (back) went 1-for-3 with an RBI single in his first rehab assignment for Triple-A Fresno on Monday night at Sacramento. ... Giants CF Angel Pagan was sent to Arizona to resume his rehabilitation from a nagging back injury.