ANAHEIM -- Jordan Walden is accustomed to heaving fastballs in the 96-101 mph range. Required on Sunday to throw a strike at a significantly reduced speed to a moving target in order to facilitate a potential game-ending double play, Walden delivered the season's most damaging wild pitch.
The Angels' closer hesitated, losing his release point, and a game so vital to the Angels' slender postseason hopes seemingly sailed out into center field with his errant throw to second base.
Letting a three-run ninth-inning lead get away, the Angels were stunned by the A's, whose 6-5 victory in front of 40,794 at Angel Stadium left the Angels on life support in their bid for the American League Wild Card berth.
With Boston's split against the Yankees in a doubleheader in New York, the Angels stand three games back of the Red Sox with three left. The Rays, with a victory against the Jays, climbed to within a one game of Boston.
"I let the team down," Walden said, taking this crushing loss personally. "We battled all day. I lost the game for us."
Peter Bourjos delivered a clutch two-out, two-run single in the eighth inning to provide Walden with a three-run cushion. But when his throw to Erick Aybar, covering second on Adam Rosales' sharp grounder, deflected off the shortstop's glove, one run scored. Kurt Suzuki's opposite-field RBI double tied it at 5, leaving runners at second and third with one out.
After Jemile Weeks was walked intentionally, southpaw Hisanori Takahashi was summoned. Coco Crisp's sacrifice fly delivered Rosales with the decisive run.
Andrew Bailey claimed the save for Fautino De Los Santos, who yielded the hit to Bourjos. Walden fell to 5-4 with his 10th blown save in 42 efforts.
"On the mound," Walden said, "your arm is one speed all the time, max effort. It gets tough when you know you've got to take off a little to throw it [to a base]. It's different. No excuses. My arm dropped a little and it sailed a little. My hand probably got on the side of the ball too much.
"I knew exactly what was going on. I knew I was working with Aybar. He was coming across. It was me. The ball was hit back to me so hard, so quick. I hesitated a second and the ball just sailed on me.
"I've got to get ready for [Monday], to redeem myself."
The Rangers arrive for the regular season's final three games. Texas is preparing for the postseason. The Angels need help from the Orioles, who entertain the Red Sox, and the Yankees, who venture to Tampa Bay.
In what might have been his final start in an Angels uniform, Joel Pineiro silenced the A's for 6 1/3 innings. But those final eight outs proved elusive.
The A's rallied for a pair of eighth-inning runs against Bobby Cassevah and Scott Downs before Walden slammed the door, retiring Hideki Matsui.
In the ninth, Josh Willingham unloaded his 28th homer, a solo shot on a full count. Scott Sizemore and Chris Carter then singled. This brought up Rosales and his .073 batting average.
The Angels had huddled at the mound, and it was determined that Aybar would be the cover guy on a grounder to Walden.
That was clear to Walden, Aybar and second baseman Howard Kendrick, who was on the move. Kendrick actually pointed toward Aybar as Walden made the play.
"I had it [covered]," Aybar said. "It hit the tip of my glove. We have to forget today and try to win three games."
Angels manager Mike Scioscia acknowledged Walden's "poor throw" but refused to cast full blame on the closer.
"Erick was right in the frame where he needed to be," Scioscia said. "If he throws it where he needs to, it's a non-issue. You're throwing it to the bag.
"If we don't reach our goal, it's certainly not on Jordan or one play. We did a lot of things right on the field today. It's a heavy page, but we have to turn it now."
A's manager Bob Melvin relished the victory.
"That's a team that's really good at home, that's fighting to stay in this thing," Melvin said. "Probably the best win to this point that I can think of for us."
Kendrick, Bobby Abreu and Vernon Wells generated offense against A's starter Rich Harden.
Pineiro held the A's to three hits and no walks, striking out four. He retired the first 13 hitters before David DeJesus' infield single in the fifth. He was quickly erased on a double-play grounder.
Pineiro departed after one-out singles by Crisp and Hideki Matsui in the seventh.
Cassevah retired Willingham on a popup. Pinch-hitting for DeJesus, who sustained a right hip contusion robbing Kendrick of extra bases in the fifth inning, Michael Taylor grounded out.
Downs, who hadn't yielded a run at home in 27 previous appearances, entered following Scott Sizemore's leadoff single against Cassevah in the eighth. Pinch-hitter Jai Miller singled with one out and Suzuki, also pinch-hitting, walked on four pitches.
After Jemile Weeks singled home Sizemore, Crisp's sacrifice fly brought the A's to within a run. And in came Walden to douse the blaze against Matsui.
Harden held the Angels to three runs in six innings. Kendrick banged a one-out triple off the center-field wall in the first, and Abreu singled him home.
Abreu cracked a solo homer to right in the third, his eighth dinger of the season. In the sixth, Wells crushed his 25th homer -- and seventh in 20 games -- to left.
"We've still got life," Angels clubhouse leader Torii Hunter said. "This game hurts, but at the same time, we're still breathing."
Lyle Spencer is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.