SAN FRANCISCO (AP) Sean Murphy started things off in the ninth inning with a home run and Mark Canha had one thought: ''Here we go again!''
Down to his final strike, Canha became the latest Oakland slugger to deliver a dramatic late-game hit.
''Obviously trying to go deep, just hit a homer and let's win this game,'' Canha said of his focus.
A night earlier, Oakland erased a 7-2 deficit to win 8-7 in 10 innings after Stephen Piscotty's tying grand slam in the ninth. The A's are 15-6 and have a three-game winning streak.
''These last two nights have been incredible,'' pitcher Sean Manaea said. ''You can't really beat those kinds of wins. It's been a lot of fun.''
Oakland is quickly making a habit of fabulous finishes much like last year - already with two walkoff grand slams.
Marcus Semien hit a two-run homer and Matt Olson also connected for the A's, who won for the 12th time in 14 games.
''We have a deep lineup. I've said it often we can score anywhere one through nine,'' manager Bob Melvin said. ''When we get guys on base we have a good feeling. I don't know how many times I've said this, our best at-bats come late in games.''
Darin Ruf put San Francisco ahead 6-3 with a three-run shot in the seventh before the bullpen squandered it again.
Trevor Gott (1-1) surrendered Murphy's leadoff homer in the ninth that started the latest A's rally and a one-out double to Tony Kemp before walking Matt Olson, bringing up Canha.
T.J. McFarland (2-0) recorded the final out of the eighth for the victory before Liam Hendriks closed it out for the second straight game and his seventh save.
Giants starter Kevin Gausman struck out a career-high 11 over 5 2/3 innings. It marked his fourth double-digit strikeout game and first since April 17, 2019, against Arizona while with the Braves.
Mike Yastrzemski hit a two-run triple in the fourth before scoring on shortstop Semien's wild throw past Gold Glove third baseman Matt Chapman.
''It's very difficult to deal with the last couple losses,'' Giants manager Gabe Kapler said. ''It's part of baseball but at the same time I think it's appropriate to feel the sting and to acknowledge the sting. Beyond that, I know we have better baseball in us.''
Olson tied it in the sixth. Of his seven hits in 43 at-bats over his last 11 games all of those have cleared the fences.
Manaea started a day earlier than scheduled for Oakland but is still searching for his first victory of 2020. He went 4-0 last September upon returning from shoulder surgery before losing the AL wild-card game to Tampa Bay.
A's infield prospect Vimael Machin, the designated hitter as Khris Davis got most of the day off, singled leading off the third for his first major league hit. He scored on Semien's homer.
MANAEA BY THE NUMBERS
Manaea reached five innings for the first time over his initial five starts and his first outing not surrendering four or more runs.
That such streak of not getting through the fifth and giving up at least four runs was the second-longest to begin a season in A's history - with the only longer stretch being five by Rick Langford in 1983.
Manaea has allowed 20 runs so far.
Athletics: RHP reliever Burch Smith is likely headed to the injured list after straining his right forearm. He will have an MRI on Monday. ... RHP opening day starter Frankie Montas was scheduled to play catch a day after he woke up with the stiffness in his back and lower neck and was scratched from his scheduled start. While he was better, manager Bob Melvin said it wasn't worth pushing him and Montas would likely throw off a mound before pitching again - ''Tuesday at the earliest'' in Arizona, Melvin said. ... LHP A.J. Puk, on the injured list and yet to appear this season because of a strained pitching shoulder, threw a 20-pitch bullpen Friday and is set for a 30-pitch session Monday. ''They have it all mapped out,'' Melvin said.
Giants: OF Austin Slater returned to the lineup leading off as the designated hitter after missing the previous two games with a strained right elbow.
RHP Logan Webb (1-1, 2.81 ERA) pitches the series finale for San Francisco opposite A's RHP Mike Fiers (1-1, 6.86).
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