The veteran shortstop was fortunate to make the postseason roster, then had only two at-bats in the Division Series against Atlanta.

“He was kind of forgotten,’’ Giants closer Brian Wilson said. “But that’s the kind of team we have, guys who don’t panic and are waiting for the right moment.’’

That moment came in the seventh inning of Game 5 in the World Series last night. Renteria made history again, coming to the plate with two on and two outs and driving a Cliff Lee pitch over the wall in left-center field. His home run helped the Giants to a thrilling 3-1 victory and their first championship since 1954.

Tim Lincecum went eight innings for the victory before turning the game over to Wilson, who struck out Nelson Cruz to end it.

Cue the party in San Francisco; the city that lured the Giants away from New York in 1958 but had not won a title until last night.

“It’s unbelievable,’’ said Renteria, who was named Most Valuable Player. “That’s life. I’ve been hurt all year but I kept myself in shape, kept working hard, and I kept telling myself to be patient.’’

Renteria was 22 when he had the game-winning hit in the 1997 World Series for Florida. He also holds a prominent place in Red Sox history, grounding into the final out of the 2004 Series while playing for St. Louis.

The Sox signed Renteria to a regrettable four-year, $40 million deal that winter, then traded him a year later. Now, improbably, he is a champion again.

Only Renteria, Lou Gehrig, Joe DiMaggio, and Yogi Berra have had game-winning RBIs in two clinching World Series games.

“Edgar has been through it and I wanted a leader out there,’’ said Giants manager Bruce Bochy, who inserted Renteria into the lineup starting in Game 3 of the National League Championship Series. “What a pro he’s been through all this.’’

The starters dominated the first six innings, Lincecum allowing two hits and Lee three. Neither team was able to advance a runner beyond first base.

The tenor of the game changed sharply in the seventh. The Giants started the inning with singles up the middle by Cody Ross and Juan Uribe. Aubrey Huff then put down the first sacrifice bunt of his 11-year career.

Pat Burrell struck out, foiling that strategy. But he saw seven pitches, giving Renteria a chance to assess what Lee still had.

Watching from the on-deck circle, Renteria told himself to wait for Lee’s cut fastball and try to drive it up the middle. Earlier in the inning, he told teammate Andres Torres that he would hit that pitch out if Lee threw it.

“He tried to throw the cutter and the cutter stayed in the middle,’’ Renteria said. “That’s why it went out.’’

Renteria was 7 for 17 in the Series with two home runs, six RBIs, and six runs scored. He hit three home runs during the regular season.

Lincecum, who beat Lee twice in the Series, was brilliant. He scattered three hits, walked two, and struck out 10. Pitching coach Dave Righetti challenged him to match the performance of rookie Madison Bumgarner, who held Texas scoreless for eight innings in Game 4 Sunday night.

“That was part of it,’’ said Lincecum, who used his slider effectively. “This was a big game and I had to throw up some zeroes.’’

The Rangers, one of the best offensive teams in baseball, went out with a whimper. Texas scored one run over the final 21 innings of the Series and hit .190 for the five games. After winning Game 3, Texas advanced only two runners as far as second base.

“Their pitching certainly stood up and that was the difference right there,’’ Rangers manager Ron Washington said.

Texas scored its run in the bottom of the seventh on a home run by Cruz. But Lincecum retired the final five batters he faced before turning the game over to Wilson, the eccentric righthander with the goofy black beard.

After striking out Cruz to end it, Wilson crossed his arms in memory of his deceased father, then was swarmed by his teammates.

“We play baseball with the understanding that the team that gives up the least amount of runs wins the game,’’ Wilson said. “That’s the point of our team, pitching.’’

A native of Londonderry, N.H., Wilson grew up dreaming he would play for the Red Sox in the World Series.

“Then the Giants drafted me and I thought I might as well do it for this team,’’ he said. “You know what? It’s fantastic.’’