SOUTH WILLIAMSPORT, Pa. — California's mini-mashers bashed their way into the Little League World Series championship tonight.

Andy Rios hit a grand slam in Chula Vista's nine-run first inning and the Cali sluggers routed San Antonio, Texas, 12-2 to advance to Sunday's final against Taiwan.

"USA!, USA!" the frantic California fans chanted after their team won the U.S. bracket.

Chula Vista will try to extend the United States' four-year winning streak in the World Series title game. Taiwan advanced with a 9-4 victory over Mexico.

Luke Ramirez and Bulla Graft also hit consecutive homers in the first, and Graft added a two-run drive to center in the third. California has 19 homers in five World Series games.

Rios got Chula Vista off to a fast start with a terrific play at shortstop in the top of the first, leaping to his right to stab Travis Daves' liner before starting a double play.

Ramirez also was impressive on the mound, throwing one-hit ball in a game that was shortened to 3½ innings because of the 10-run rule. After fanning Troy Montemayor for the final out, the imposing 6-foot Ramirez pumped his arms, then pointed skyward and let out a big yell.

The 13-year-old slugger has turned into a star in Pennsylvania, with fans chanting "Luuuuke!" each time he steps to the plate. They were still hooting and hollering his name 15 minutes after the game was over, with the rest of the stadium mostly empty.

"I can't explain the feeling," Ramirez said. "We've been together since we were like 7 or 8. We're all brothers out there so it's great to share this."

It will be the first appearance for a California team in the World Series final since 2004, when Thousand Oaks lost to Curacao.

Texas lost for the first time this year. It was held scoreless until the fourth, when Jacob Ramos had an RBI double and another run scored on a passed ball.

Manager Mike Shull wasn't worried about how his team would handle the loss.

"I'm sure they're over it now," he said. "I'd be willing to bet they're up in the (recreation) room now waiting for Chula Vista to beat them in pingpong."

Taiwan 9, Mexico 4

The smiling boys from Taoyuan, Taiwan stood along the third-base line and took a bow in unison as their parents and fans snapped pictures.

They had plenty to be excited about after winning a spot in the World Series title game.

Taiwan took advantage of six Mexico errors and scratched out runs on a bunt single and a bases-loaded walk to take the international title. Taiwan is back in the title game for the first time since 1996, when it beat Cranston, R.I.

"I was really excited, but tomorrow we have another game — the championship game," starting pitcher Wen Hua Sung said through translator Ming Huang Yeh.

A mix of Mexico miscues and six-hit pitching by the 12-year-old Sung lifted Taiwan in a game delayed twice by rain.

Mexico waited out the delays in the dugout by reminiscing about its fun times in Pennsylvania.

Some Taiwan players spent the time practicing their swings or snacking on chocolates. Sung went over his pitching motion to stay loose, and his concentration paid off.

Manager Chen Ta Lee said he set up his rotation to have Sung pitch the international final.

Chin Ou scored on a bases-loaded walk in the fourth inning, then smacked a two-run double in the sixth to give Taiwan a four-run cushion.

Trailing 9-2 entering the sixth, Mexico got two runs on a groundout and an infield single by Marcelo Martinez before Sung struck out Allan Wilburn to end it.

The teams then exchanged customary Little League postgame handshakes at the plate, before Taiwan lined up to take its bows.

But it was hard to tell that Mexico lost when the skies opened up again as soon as the game ended and the grounds crew hurried to cover the infield.

The squad of 12- and 13-year-old boys danced in the showers, and some opened up their jerseys and started belly flopping and sliding on the waterlogged tarp to the delight of the crowd.