OAKLAND -- A back-and-forth affair at the Coliseum went in favor of the A's, who staved off the Yankees with a walk-off, two-run single from Khris Davis in the 10th inning to claim an 8-7 series-opening victory on Thursday night.
The rally against Yankees right-hander Giovanny Gallegos began with two outs, when Rajai Davis singled and Chad Pinder followed with a double. New York elected to intentionally walk Jed Lowrie, who stepped to the plate a double shy of hitting for the cycle, and instead faced Khris Davis, who sent a flare over second baseman Starlin Castro for the game-winning hit.
"I thought it had a chance, but Castro was getting after it out there, so you never know," Khris Davis said. "I saw it tip off his glove and then I saw my boys running after me, so that was fun."
This, after the Yankees had erased four A's leads, with Gary Sanchez and Chris Carter each recording a pair of game-tying hits, and Castro hitting a go-ahead sacrifice fly against Liam Hendriks in the 10th.

"It was 10 innings, and it felt like 15," A's manager Bob Melvin said. "There were so many emotional swings in the game and it just kind of wears you out a little bit. That was a great baseball game for any baseball fan, either side, watching that game. Every time a team had a lead, it looked like they had the advantage, and the next team came up and scored again. Look at the line after the fifth inning, and it was an absolute back-and-forth game, so give our guys a lot of credit to hang in there."
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Oakland carried a 3-0 lead against Yankees starter Jordan Montgomery after five innings, but New York proceeded to tie the game in the sixth, seventh, eighth and ninth innings. The trend began opposite A's starter Sonny Gray, who allowed three runs in the sixth on back-to-back RBI hits to Chase Headley and Carter, prompting his exit with just one out.
Yonder Alonso notched his 17th home run in the bottom half of the frame to put the A's ahead, 4-3, but the Yankees got a game-tying double from Sanchez against Ryan Madson in the seventh. Pinder put the A's back on top in the bottom half of the inning courtesy of an RBI base hit, before Carter was at it again, homering off of John Axford.

Alonso scored another run in the eighth for a 6-5 lead, but Sanchez bit again in the ninth with a single against A's closer Santiago Casilla that plated Castro, who reached on a one-out double.
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"We kept fighting back. We got behind then we tied it up, got behind, tied it up," Yankees manager Joe Girardi said. "We did it a bunch of times. It hurts because it's a matter of a couple inches that you lose that game by and it's frustrating."
The A's left the bases loaded in the ninth against Dellin Betances and were one out away from doing so again in the 10th, before Khris Davis delivered his third career game-ending hit.

"As soon as he hit it, I was like, be a thing, be a thing," Alonso said. "Hopefully it can get down and we can go home with a win. That's the definition of a team win right there."
MOMENTS THAT MATTERED
Chapman debuts, walks: A's third baseman Matt Chapman stepped to the plate with two outs in the second inning for his first big league plate appearance, drawing a five-pitch walk that set the stage for a two-run inning. Following Chapman's walk, Josh Phegley put the rookie on third base with a ground-rule double, and Adam Rosales brought them both home with another double to extend Oakland's lead to 3-0. Chapman, promoted from Triple-A Nashville earlier in the day, finished 0-for-3 with two walks. More >
"What a wild first game," Chapman said. "It was awesome being part of that."

Re-Joyce: Alonso singled off former Athletic Tyler Clippard to lead off the eighth, setting in motion another pivotal inning for the A's. Ryon Healy struck out, but Chapman drew a walk to put runners on second and force Betances into the game. Betances walked Stephen Vogt to load the bases for Matt Joyce, who slid headfirst into first base to avoid a potential inning-ending double play and allow Alonso to score for a temporary 6-5 lead.

QUOTABLE
"It's been a tough grind here. The guys have played extremely hard. We've had some long games and some late nights and you have to fight through it." -- Girardi on Yankees' three-game losing streak, with two coming in extra innings
WHAT'S NEXT
Yankees: Right-hander Luis Severino (5-2, 2.75 ERA) will head to the hill Friday for the Yankees as they face the A's at 9:35 p.m. ET at the Coliseum. Severino is 3-0 with a 1.27 ERA in his last four starts, striking out 30 in 28 1/3 innings.
A's: The A's will send lefty Sean Manaea (6-3, 3.67 ERA) to the mound for Friday's 6:35 p.m. PT matchup with the Yankees at the Coliseum. Manaea is 5-0 with a 1.97 ERA and .193 opponents average over his last five starts.
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