The A's scored twice in the ninth with two outs off closer Mark Melancon to tie it at 3.
After San Diego scored a run in the top of the 10th off Lou Trivino (4-4) to take a 4-3 lead, Olson came to the plate with runners on the corners and no outs.
“Honestly, I thought it was a sac fly," Olson said. "It carried pretty well for Oakland standards, I think. ... It kept on going and Marte got off well and made a great read on it.”
Oakland posted its AL-leading ninth walk-off win of the season. It's the team's 92nd walk-off win since Bob Melvin became manager in 2011, the most in the majors during that span.
“The expectation level is really high for us late in games," Melvin said. "I think any time we get in a position where we feel like we have a chance to win the game here at home with the last at-bat, we always feel good about it.”
“We just couldn’t get the 27th out today," San Diego manager Jayce Tingler said. "You’ve got to give Oakland credit as well. They put together some tough at-bats there late and were able to find some holes and get the ball in play.”
San Diego starter Joe Musgrove limited Oakland to one run on two hits in six innings.
DAVIS BACK WITH A’S
Before the game, Oakland signed veteran DH Khris Davis to a minor league contract. The 33-year-old spent five seasons with the Athletics, hitting 158 home runs, before being traded to the Texas Rangers last offseason. He was designated for assignment in June after batting .157 with two homers and five RBI in 22 games.
“We love having him back in the organization,” Melvin said. “It’s giving an opportunity for him to get back to where he was in the past.”
Davis surpassed the 40-homer mark in three straight seasons from 2016-18, including a league-high 48 in ’18. He signed a two-year, $33.5 million contract extension in ’19 but struggled with injuries and performance the next two years. Still, Melvin is hopeful Davis can regain his form.
“It’s not like he’s 40 years old,” Melvin said. “We signed him back with the hope and intent that he starts hitting some longballs and maybe can help us out here at some point.”
Davis was assigned to the Athletics’ Arizona Complex League roster.
Padres: RHP Dinelson Lamet (right forearm inflammation) is scheduled to begin a rehab assignment with Low-A Lake Elsinore on Wednesday night. Lamet has been on the injured list since June 27, his third IL stint of the season.
Athletics: RHP James Kaprielian (right shoulder impingement) played catch before Wednesday’s game and could start Sunday against Texas. “It’ll either be he or Daulton (Jeffries), depending on how he feels,” Melvin said. “But he felt a little bit better today.”
Padres: LHP Ryan Weathers (4-3, 3.65 ERA) looks to bounce back from a rocky outing as San Diego welcomes the Arizona Diamondbacks for a three-game series beginning Friday night. He allowed eight earned runs in four innings last Friday in a 9-4 loss to the Colorado Rockies.
Athletics: RHP Chris Bassitt (11-3, 3.28) takes aim at an AL-leading 12th win Friday night as Oakland hosts the Texas Rangers for a three-game series. Bassitt is 3-0 with a 0.86 ERA against Texas this season.
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