(AP) Josh Donaldson hit a two-run homer to back Dan Straily's strong start, and the Oakland Athletics beat the San Francisco Giants 4-1 in the Bay Bridge Series opener Monday.
Straily (3-2) tossed six innings of one-run ball, allowing four hits and one walk. Buster Posey's groundout in the sixth inning drove in San Francisco's lone run.
Donaldson connected against Madison Bumgarner (4-3) in the fourth, and Yoenis Cespedes added a two-run double against George Kontos in the seventh to extend Oakland's lead.
Sean Doolittle pitched two perfect innings and Grant Balfour recorded his 11th save of the season for Oakland, which has won four straight and nine of 10.
The usual sprinkling of green-and-gold clad fans mixed with San Francisco's orange-and-black following that traveled from across the bay to pack Oakland Coliseum. The announced sellout crowd of 36,067 traded chants of "Let's go Oakland!" and "Let's go Giants!" throughout the cloudy afternoon.
Straily retired 14 of his first 15 batters and looked confident and in control from the start. Bumgarner struggled with his command matching a career high with five walks but didn't allow a hit until the fourth.
That hit turned out to be the difference.
Donaldson sent a cutting 89 mph fastball over the right-center field wall to give the A's a 2-0 lead. Donaldson raised his right hand in the air after jogging around first base, celebrating his eighth home run with a little extra flair.
Bumgarner struck out six, was tagged for all four runs and also hit a batter in 6 2-3 innings. The lefty has lost three of his last four starts.
San Francisco squandered its best chance for a big inning when Posey grounded out in the sixth to score Gregor Blanco, snapping Straily's scoreless streak at 12 1-3 innings. Then Straily snared Hunter Pence's grounder to strand Marco Scutaro on third.
It was Straily's second straight scintillating start. He tossed seven innings of two-hit ball in a 1-0 win over Texas last week.
Oakland's bullpen backed up his outing far better than San Francisco's did for Bumgarner, who was relieved after walking Chris Young with two outs in the seventh. Cespedes followed with a towering double off the right-center field wall that put Oakland up 4-1, ending the little drama left.
NOTES: Giants reliever Santiago Casilla said he will have surgery Tuesday to remove a cyst from inside a bone in his right leg. He hopes to return just after the All-Star game on July 16. ... Oakland RF Josh Reddick, on the disabled list since May 8 with a sprained right wrist, began a rehab assignment Monday night at Class-A Stockton. He will shift to Triple-A Sacramento on Tuesday, where he will likely be at least three days, A's manager Bob Melvin said. ... Giants CF Angel Pagan (sore left hamstring) sat out for the second straight day but hopes to be back in the lineup Tuesday. ... Lefty Michael Kickham will be called up from Triple-A Fresno to make his major league debut for the Giants on Wednesday against Oakland RHP Jarrod Parker (2-6, 5.76 ERA). He takes over the spot in the rotation vacated by Ryan Vogelsong, who fractured his right hand when he was hit by a pitch May 20.