Madison Bumgarner turns up big for Giants

These San Francisco Giants have not known the joy of clinching a postseason series at home, of prancing giddily around the field, of spraying their fans with assorted liquid substances.

They might never know that joy. They would happily pay that price in order to win the World Series on Monday.

The Giants are one victory from a championship. Never have they won a Series in San Francisco.

But never in their San Francisco history have they led a Series three games to one. They do now, thanks to a pitcher of legal drinking age for all of three months.

Madison Bumgarner, at 21 the youngest pitcher to start a Series game since Fernando Valenzuela in 1981, pitched eight scoreless innings to lead the Giants to a 4-0 victory over the Texas Rangers on Sunday.

He allowed one runner past first base.

“He’s an amazing kid,” said Brian Sabean, San Francisco’s general manager. “He’s got an innate sense of courage.

“At this age, he is a genius right now, with what he’s doing. He’s not really aware of his surroundings.”

The only younger pitcher to throw at least eight scoreless innings in a Series was Hall of Fame member Jim Palmer, who shut out Sandy Koufax and the Dodgers in 1966.

“That’s pretty awesome, to be mentioned with those guys,” Bumgarner said.

Aubrey Huff, who grew up rooting for the Rangers, wounded his hometown team with a two-run home run. Buster Posey homered too, and shepherded the Giants’ second shutout in three games.

Posey, 23, and Bumgarner started the season as teammates at triple-A Fresno. The two teamed up Sunday as the first rookie battery to start a Series game since 1947.

The Giants clinched the National League division series in Atlanta. They clinched the NL Championship Series in Philadelphia.

They can clinch the Series on Monday, in Texas, and they have the rotation aligned just the way they want. Their Game 5 starter is their ace, two-time defending Cy Young Award winner Tim Lincecum.

Bumgarner, starting for the first time in 11 days, chilled the Rangers on three hits — all singles — through eight innings.

With two out in the seventh inning, the Rangers got their first runner into scoring position, bringing the potential tying run to the plate. Ian Kinsler struck out, and through seven innings Bumgarner still had not thrown 100 pitches.

In the hours before the most important start of his career, Bumgarner said he hung out with his family, watching football at the team hotel.

“He’s fearless, man,” Huff said. “He came to the yard and you could see he was just chilling. Nothing really bothers him. Put some David Allan Coe on the playlist and let him go to town.”

The Giants could close out the season Monday. This is a big deal, even though the unusually calm Bumgarner gives off the appearance of not knowing just how big.

“It may hit him this off-season,” pitcher Jeremy Affeldt said. “We’re supposed to go hunting. I might remind him about this. Right now, I’d rather he be unconscious.

“Hopefully, we can go home with a ring.”

bill.shaikin@latimes.com