OAKLAND -- The A's used their power to erase a four-run deficit, their bullpen to keep them afloat and a dose of extra-inning, Boog Powell-fueled energy to christen the 2018 season with a walk-off win on Thursday afternoon.
The speedy Powell, enjoying his first Opening Day start, tripled with one out in the 11th and scored on Marcus Semien's game-ending single for a thrilling 6-5 victory over reliever Noe Ramirez and the Angels at the Coliseum.
"Guys were mentioning that he was getting on them a little bit with his fastball, but he didn't throw it," Semien said. "He threw changeups and sliders."

Staring down a five-man infield after an intentional walk to Matt Joyce, Semien pounced on a changeup, slapping a single into center field for his first career walk-off hit.
"Kind of like a field goal, just hit it right in the middle," Semien said.

It capped an encouraging team effort, following a less-than-stellar outing from starter Kendall Graveman, who was tagged for three homers. The right-hander allowed five runs in five-plus innings, while counterpart Garrett Richards was also victimized by the long ball in his five-inning stint.
A's sluggers Khris Davis and Matt Olson teamed up for back-to-back homers in a lively four-run fifth inning that tied the game, before Jose Pujols' sixth-inning leadoff shot for his 615th career home run temporarily put Los Angeles back on top and nearly made a winner out of Richards.

But Davis had other ideas, picking up his fourth RBI of the day with a game-tying single against right-hander Cam Bedrosian in the seventh. A battle of the bullpens ensued, before Oakland emerged victorious in front of the home crowd.
"We've seen some walk-offs here in the past, but that was a little bit excruciating," A's manager Bob Melvin said, smiling. "One, it's tough dealing with Opening Day because you want to make a good impression and you certainly want to win the game. There's a little more nerves, and to have to wait that long makes it a little more excruciating, but at the end of the day, a win is a win. It's nice to come back after being down like we were, too. Down four and their guy's rolling pretty good, the next thing you know it's 4-4. The guys fought for 27 for sure, more than that."

MOMENTS THAT MATTERED
Homer happy: Perhaps the A's biggest weapon is their power. It's sprinkled throughout a deep lineup, looming big time in the middle. That's where Davis and Olson, who combined for 67 home runs last season, reside. They woke up the crowd with back-to-back shots off Richards that changed the course of this game.
"[Davis] said something about the Bash Brothers earlier, but I'm not going to go that far," Olson said. "But it's fun. I always like getting that on-deck view of him. He's obviously a talented hitter with a lot of power, so to follow that up is nice."
Added Melvin: "The power in the middle of the order is going to be significant in games like that. When you're down and you have guys on base, you can put some runs on the board in a hurry, and that was the case today."

Relieved: The A's spent much of their offseason retooling their bullpen, and two of their key additions played a vital role in the season opener. Following Graveman's departure, lefty Ryan Buchter struck out two in a scoreless inning, paving the way for two shutout frames from veteran righty Yusmeiro Petit as the A's staged a comeback. Closer Blake Treinen kept it going with two clean innings, and Chris Hatcher capped the bullpen's effort by striking out Michael Trout to strand two in a scoreless 11th.
"I think we did exactly what they built this bullpen for, to be able to eat some innings and at the end of the game close it out," Hatcher said. "Yusmeiro did his job, Blake did his job, and I was just fortunate to do my job." More >

QUOTABLE
"I believe that. I would say we all have those games, but obviously he's never had one. That's tough to believe, though. He's the best player in the game. It was bound to happen at some point." -- Hatcher, on Trout going hitless in six at-bats for the first time in his career

SOUND SMART WITH YOUR FRIENDS
The A's, who opened their 50th anniversary season on Thursday, played the Orioles in their first game at the Coliseum in 1968. The player to score the first run in that game was Baltimore first baseman Boog Powell. Thursday's winning run was scored by the other Boog Powell.

WHAT'S NEXT
Angels:Tyler Skaggs will start the Angels' second game of the season against the A's on Friday at the Coliseum. Ian Kinsler, who sat out the season opener with a groin injury, is also expected to make his Angels debut at second base. First pitch is scheduled for 7:35 p.m. PT.
Athletics: The A's will have left-hander Sean Manaea on the mound for Friday's matchup against the Angels, deemed "Opening Night" in Oakland. First pitch of the second game of this four-game series is scheduled for 7:35 p.m. PT, following a special pregame ceremony honoring members of the A's 50th anniversary team.
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