OAKLAND, Calif. -- The collision of two of baseball's hottest teams ended with a four-game knockout.
What had been two of baseball's hottest teams, anyway.
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The Athletics ended a nine-game Coliseum losing streak to the Yankees on Thursday night with the first of four one-run wins, culminating with Oakland's 5-4 victory in 12 innings Sunday that completed a four-game sweep.
"We ran into the Green Machine over there," Alex Rodriguez said. "Those guys are playing good baseball, pitching well. Everything they're doing is working out well for them."
The Yankees (57-38), who had won eight of 10 coming into this series and had a 10-game lead in the AL East, saw the Orioles climb within six.
"We lost four tough games by a total of four runs and that's no fun," manager Joe Girardi said. "But we have to put it behind us and get ready for Seattle."
The Yankees, who led 4-0 going into the bottom of the fifth Sunday, start a three-game series in Seattle Monday night.
They were on the verge of victory until Rafael Soriano, 24-for-25 in save chances coming in, blew the save in the ninth by allowing his first home run of the year, a one-out blast to center by Seth Smith that tied it at 4.
"Everybody has bad days and today was the second time it happened," Soriano said. "So what? You have to come back tomorrow and prepare to go 1-2-3."
The A's, who won it on Coco Crisp's two-out single off righthander Cody Eppley, improved to 51-44 and notched their MLB-leading 11th walk-off victory -- they won Friday's game on Brandon Moss' walk-off RBI single, also against Eppley.
"We were playing pretty good coming in here but those guys have been playing good," Derek Jeter said. " . . . They're playing with a lot of confidence."
The A's are a major-league best 14-2 in July, including 8-1 since the All-Star break.
Crisp's single brought in Derek Norris, who reached when Jeter couldn't handle his ground smash -- the play was scored a hit -- and went to second on a sacrifice bunt.
"Just kicked up," Jeter said of an infield Mark Teixeira compared to fielding "on a parking lot" during day games here. "It hugged the ground pretty much the whole way and bounced up at the last second."
The Yankees had a chance in the top of the 12th when Teixeira led off and reached second on a fly ball rightfielder Josh Reddick lost in the sun. But he was stranded as the Yankees went 3-for-11 with runners in scoring position and left 11 on base.
"You don't expect to lose any series the way we've been playing. We've been playing some really good baseball," Teixeira said. "It's just very disappointing to lose four in a row."
Suzuki's home run was his first of the year, fifth career blast against Sabathia and snapped a 78-game homerless streak. "They're tough," Sabathia said. "Anytime they get in position, they feel like they can win or come back, and it's tough facing a team like that."
Jayson Nix, starting for Jeter at short, bobbled the start of what might have been a 6-4-3 double play in the sixth, leading to the A's third run, which made it 4-3. "When you don't make a play that should be made," Nix said, "it's frustrating."
The word of the day for the Yankees. The last four days, in fact.