NEW YORK -- Joe Torre's filly broke late from the gate. His baseball team stumbled at the finish.
From Churchill Downs to Yankee Stadium, it was a bitter day for the New York manager.
"It's a tough game because you play every day when you're doing badly," Torre said.
Barry Zito pitched effectively into the eighth, and Oakland got home runs from Eric Byrnes and Bobby Kielty to end a three-game skid and leave New York with its worst 30-game start in 39 years.
Torre watched on TV in his clubhouse office as his heavily favored filly, Sis City, finished fourth in the Kentucky Oaks about 90 minutes before the game.
The Yankees will have an eye on Churchill Downs on Saturday, too: George Steinbrenner owns Kentucky Derby favorite Bellamy Road.
But on the baseball field, the $200 million Yankees look nothing like thoroughbreds.
They have lost four straight and eight of 10, leaving them tied for last place in the AL East with Tampa Bay, nine games behind first-place Baltimore. New York is 11-19 for the first time since 1966.
The Yankees are also eight games under .500 for the first time since June 21, 1995, when they were 21-29 after winning that day, according to the Elias Sports Bureau.
New York made three errors in the 10th -- two on one play by first baseman Tino Martinez.
"A lot of things have not been going our way, and some things finally did," Oakland's Scott Hatteberg said. "We need confidence wherever we can find it. There's no better place than beating the Yankees, especially in this fashion."
Rivera (2-2) issued a leadoff walk to Marco Scutaro and, one out later, hit Jason Kendall with an 0-2 pitch.
"That ball just took off. I don't have an explanation," Rivera said.
Eric Chavez's infield single loaded the bases, and Hatteberg hit a one-hopper that Martinez knocked down. But he failed to step on the bag as he made an ill-advised throw to the plate, which earned him his first error.
Martinez had little chance to get Scutaro, and his throw was way wide for a second error, allowing another run to score.
"I've got to make that play. Once I booted the ball, my whole thought process was, get the out at home," Martinez said. "That play, in my mind, cost us the game. I probably had a little more time than I thought."
After a two-out error by third baseman Alex Rodriguez, Rivera forced in a third run with a walk to Keith Ginter.
Oakland batted around against Rivera, who pitched more than one inning for the first time this year.
"This is no time to rest or sit around and wait for things to happen," he said.
Octavio Dotel (1-0) worked 1 2/3 hitless innings for the win, and Kiko Calero got two outs for his first save.
Zito took a 3-1 lead into the eighth before the Yankees rallied.
Pinch-hitter Jorge Posada delivered an RBI single, cutting it to 3-2 and chasing Zito. Derek Jeter and Posada then pulled off a daring double steal, leaving runners at second and third. Jeter scored the tying run on Gary Sheffield's RBI grounder against Dotel.
But the inning ended when Posada was thrown out at third trying to advance on Dotel's pitch behind Rodriguez. The ball glanced off Kendall's mitt but didn't roll very far away.
"When things aren't going well, you tend to force them," Torre said. "He may not have gotten the jump he thought he did."
Zito had his second solid outing in a row after an 0-4 start. The 2002 AL Cy Young Award winner gave up three runs and six hits in 7 1/3 innings.
"I just need to keep in my process and eventually the wins will come. But most importantly, I think I'm on track," Zito said. "This place is just insane. You've got to rise to the occasion."
Yankees starter Carl Pavano got through seven innings with the help of two double plays. He allowed three runs, seven hits and three walks.
Hideki Matsui, in a 4-for-37 slump, hit a two-out RBI triple off center fielder Mark Kotsay's glove in the first inning to give the Yankees a 1-0 lead. Zito retired his next 11 batters before a one-out double by Andy Phillips in the fifth, but he was stranded.
Byrnes hit his third homer leading off the third. Hatteberg drew a leadoff walk from Pavano in the fourth, and Kielty drove the next pitch over the right-field fence for his second homer and a 3-1 Oakland lead.