The Little League World Series is down to its final four.

Petaluma, Calif., was one of two teams to join that exclusive group on Thursday in Williamsport, Pa., using a six-run first inning to spark an 11-1 victory over San Antonio, Texas. The West regional representatives advanced to Saturday's United States championship game, set for 3:30 p.m. ET against the Southeast's Goodlettsville, Tenn., squad.

The international championship game, scheduled for 12:30 p.m. ET on Saturday, will pit Tokyo, Japan, against Aguadulce, Panama, after the Latin American representatives pulled out a 2-1 win over Nuevo Laredo, Mexico, on Thursday.

The winners of Saturday's games will match up in the World Series championship at 3 p.m. ET on Sunday.

Shortstop Hance Smith and pitcher Danny Marzo teamed up to power California past Texas, with Smith slamming two home runs and Marzo striking out 11 in a complete game.

Smith's first homer, a grand slam, staked his team to a 5-0 first-inning lead, and Quinton Gago added a solo shot before the frame was over. Smith then ripped a solo shot of his own in the third, finishing 3-for-3 with five RBIs.

Marzo held Texas to one run on two hits and one walk, and California ended the game when it extended its lead to 10 runs in the fifth inning.

In international play, Panama's James Gonzalez smacked a two-run homer in the first inning against Mexico before his team held on for the victory. Edisson Gonzalez made it possible, twirling a one-run complete game with 11 strikeouts and no walks.

Mexico got a 12-strikeout complete game from its pitcher, Ramon Ballina, and pulled within 2-1 on Marcelo Perez's RBI single in the fifth inning. Mexico put the potential tying run at second base in both of the last two frames, but Gonzalez shut the door.