OAKLAND, Calif. — Josh Hamilton made one thing clear: The Texas Rangers will forget their stunning season-ending sweep at Oakland and regroup as an American League Wild Card.

So much for a third straight AL West crown. Texas needed one win against the upstart Athletics in three games, and didn’t get it.

“You guys have a hard time believing we can forget about it and move ahead,” Hamilton said. “But that’s what we get paid to do. We’ll go home, regroup and go figure out what we have to do.”

The Athletics captured the AL West with another improbable rally in a season full of them, coming back from four runs down and a 13-game division deficit to beat the two-time defending league champion Rangers 12-5 on Wednesday.

Hamilton dropped a fly ball in center field for a two-run error that put the A’s (94-68) ahead 7-5 in a six-run fourth inning. The A’s only added to Texas’ troubles the rest of the way.

“You can have all the experience as you want but when you run into a team that’s hot, experience has nothing to do with it,” Rangers manager Ron Washington said.

Texas (93-69) is headed to the new one-game, Wild Card playoff at home against Baltimore on Friday night, with the winner playing the New York Yankees in the division series.

The A’s get some time off before opening the division series in their first postseason appearance since 2006, playing Game 1 at Detroit on Saturday.

The Athletics needed a sweep and they delivered to win their first division crown in six years and 15th in all. They overcame a five-game deficit in the final nine days and took sole possession of the West’s top spot for the first time this year.

“We knew this is a beast of a team we would have to beat, and to be able to beat them three games in a row and win the division on top of it, really it’s a magical type thing,” manager Bob Melvin said.

Grant Balfour retired Michael Young on a fly to center for the final out, then raised his arms in the air as the A’s streamed out of the dugout and began bouncing up and down in the infield.

“2012 AL WEST CHAMPIONS” flashed on the scoreboard two days after the A’s clinched a playoff spot Monday and held a wild dance party in the clubhouse.

“I’m glad there’s not one tomorrow or Friday,” owner Lew Wolff said. “I can relax and go home. I’m running out of underwear.”

Players high-fived fans while taking a victory lap through the rundown Coliseum, where the outfield still has a light patch of grass from football in the venue shared by the NFL’s Raiders.

Soon, the celebratory champagne and beer made its way to the field — and players sprayed it into the stands. The A’s returned to the field almost an hour later to greet fans still gathered along the top of the dugout.

Oakland pulled off another remarkable performance in a season defined by thrilling walkoffs, rallies and whipped-cream pie celebrations by a team that was never supposed to be here.

A club that trailed Texas by 13 games on June 30. A club with a $59.5 million payroll, the lowest in baseball. General manager Billy Beane found ways to get a blue-collar franchise back to the playoffs for the first time since being swept by Detroit in the 2006 AL championship series.

Coco Crisp hit a tying two-run double in the fourth against Derek Holland (12-7) and Brandon Moss drove in three runs, including a two-run single in the four-run eighth.

Rookie winning pitcher Evan Scribner (2-0) left the mound in the sixth to a standing ovation from the sellout crowd of 30,067. He allowed two hits and struck out two in three scoreless innings after replacing struggling starter A.J. Griffin.

Ryan Cook, pitching for a fifth consecutive game, gave up a double to Nelson Cruz before retiring the next three Texas hitters with strikeouts of David Murphy and Mike Napoli. Catcher Derek Norris pumped his right arm as the Coliseum fans jumped to their feet.

Norris then homered leading off the bottom of the eighth for his second RBI. It was his seventh homer and Oakland’s majors-leading 112th since the All-Star break.

“Ever since Day 1 I’ve been here, it’s been, the A’s can’t compete with the payroll, can’t compete with this team or that team,” Norris said. “We’re better off if we’re down. It just gives us the extra energy.”

The A’s join the NL West champion San Francisco Giants as division champions. The Bay Area is already buzzing about a possible Bay Bridge World Series like the 1989 championship swept by Oakland, one interrupted by an earthquake.

Hamilton’s miscue while charging forward might haunt the to-be free agent if his Rangers don’t get past their Wild Card game.

“I just missed it, man,” Hamilton said.

Murphy’s two-run single highlighted a five-run third inning that put Texas in prime position.

In the fourth, Moss drew a leadoff walk and Josh Reddick followed with an RBI double. Josh Donaldson singled and Seth Smith’s base hit made it 5-3 and chased Ryan Dempster with none out and runners on first and second.

Washington turned to the lefty Holland, a starter who was tagged for four runs in the first inning of the second game of Sunday’s doubleheader with the Angels before working into the seventh.

He retired the first two batters before Crisp’s double down the right-field line.

The only other teams to come back from at least 13 games down to win the division were the 1914 Boston Braves, the 1951 New York Giants, the ‘78 Yankees and the ‘95 Seattle Mariners.

“Anything can happen in the long season,” said Rangers pitcher Yu Darvish, who will start the Wild Card game. “That’s why we play 162 games. We’re going to forget about this and get ready for the next one.”

Now, Texas has all the pressure as they try to make another run deep into October.

These are the same Rangers who twice came within one strike of the franchise’s first World Series championship before losing Games 6 and 7 to the wild-card St. Louis Cardinals. It was Texas’ second near miss in as many years after losing the 2010 World Series to the Giants.

“We have to go win that playoff game,” Napoli said. “We didn’t come here to lose. They got it done and we didn’t, plain and simple. It’s going to be a tough road.”