Yoenis Cespedes homered twice, Josh Donaldson hit a tiebreaking shot in the seventh inning and Oakland overcame a four-run deficit to beat the Yankees 7-4 Wednesday night for its fifth straight victory.
The highest-scoring team in the majors this season, the A's will go for a three-game sweep Thursday afternoon. They are 12-3 against New York since July 19, 2012.
"I think there's the sense of the way we play that we have something to prove," said Doolittle, who earned his seventh save. "We've got a little bit of a chip on our shoulder, small-market team, and we don't get a ton of national publicity. And when we get a chance to play against the Yankees on a big stage in their ballpark, guys step up."
Donaldson connected off Jose Ramirez, who was making his major league debut, and added a pair of infield singles. Cespedes also had three hits to help the A's move a season-best 15 games over .500 at 37-22, the best mark in the American League.
"We never give up," Cespedes said through a translator.
Jacoby Ellsbury had three hits, including an early three-run homer, but the Yankees matched a season worst with their fourth consecutive defeat. They've been outscored 21-0 from the seventh inning on during the slide.
Derek Jeter made a costly error and New York dropped to 1-5 on a seven-game homestand with its 12th loss in the last 16 at Yankee Stadium.
Jesse Chavez (5-3) hung around for six innings, long enough to get the win when his teammates rallied.
Dan Otero got Brian McCann on a weak grounder with runners at the corners to protect a one-run lead in the seventh. Otero also worked a scoreless eighth and Doolittle got three quick outs to extend his career-best shutout streak to 16 1/3 innings.
"Our bullpen down there is so deep and so well-rounded out that we really don't have a hole," Chavez said. "The guys come in and they attack, and I think that's why they're so good in those situations."
Cespedes started Oakland's comeback with a leadoff homer to center in the fourth. Jed Lowrie hit a deep sacrifice fly in the fifth, and Yankees starter Vidal Nuno was pulled one out shy of qualifying for a win. He left with a 4-2 lead after 92 pitches.
Cespedes hit another leadoff shot in the sixth, this one off Matt Daley barely clearing the short porch in right. Derek Norris reached on Jeter's throwing error from shortstop and scored the tying run on Alberto Callaspo's long sacrifice fly.
"We had our chances to add on and we weren't able to do it," Yankees manager Joe Girardi said. "The guys are doing everything they can, but right now we just aren't getting it done."
Just called up from the minors, Ramirez (0-1) entered in the seventh. He retired his first batter but then gave up Donaldson's 16th homer on his fifth major league pitch. The drive to left field gave the A's a 5-4 advantage.
"I was a little nervous," Ramirez said through a translator. "I wasn't really thinking about pitching tonight but I knew the chance would be there because of our bullpen situation."
Oakland has gone deep in 12 consecutive games, hitting 22 homers during that span.
"Anytime you fall behind 4-0, you don't really expect to win these games even though you might think it," Otero said. "Our offense, it's only a matter of time sometimes before they break out, and they showed it tonight again."
The AL West leaders added two insurance runs in the ninth on a hit batter and a sacrifice fly against Wade LeBlanc in his Yankees debut.
Craig Gentry made a sensational catch in left-center to rob Gardner of at least a double in the first.
Moments earlier, Donaldson hit a trickler toward third that stopped rolling right on the line just inches from the bag. The slugger clapped his hands emphatically at first base, drawing chuckles from teammates in the dugout.
"That ball didn't even get to third base," he said. "It's just one of those things where you really appreciate a hit like that."
Gentry started in place of CF Coco Crisp, given a night off to rest his nagging neck. ... Oakland has the best road record in the majors at 20-10. ... It was Cespedes' fourth career multihomer games. The other three came in June last season. ... Yankees DH-OF Alfonso Soriano, hitless in 16 at-bats, did not play. ... Masahiro Tanaka (8-1, 2.06 ERA) faces Oakland LHP Drew Pomeranz (5-2, 2.37) in the series finale.