Chicago ? Scott Podsednik made it two electrifying home runs for the White Sox – and two World Series wins.

Podsednik’s home run off Brad Lidge in the ninth inning gave Chicago a thrilling 7-6 victory over the Houston Astros on Sunday night and put the White Sox halfway to their first World Series title in 88 years.

“I don’t think anyone in the ballpark was thinking about me hitting the ball out of the ballpark,” Podsednik said.

After yet another questionable umpiring call, Paul Konerko capped a momentous week with a seventh-inning grand slam on reliever Chad Qualls’ first pitch, giving the White Sox a 6-4 lead and sparking the crowd of 41,432 to life on a drizzly, dreary night.

Closer Bobby Jenks, who earned the Game 1 save after not pitching for 15 days, couldn’t work his magic two nights in a row.

Jose Vizcaino, pinch-hitting for Adam Everett with two outs in the ninth, reached the burly reliever for a two-run, opposite-field single to left, and Chris Burke just beat Podsednik’s on-target throw to score the tying run, slapping the plate with his hand.

Podsednik perhaps was the most unlikely hero.

He didn’t have any home runs in 507 regular-season at-bats, hitting his first of the year in the division series opener against Boston.

He came up with one out in the ninth against Lidge, who hadn’t pitched since losing Game 5 of the NL championship series against St. Louis, when he gave up a mammoth three-run homer to Albert Pujols in the ninth that teammates joked rose to airplane cruising altitude.

Chicago's Scott Podsednik, center, is embraced by teammates after hitting a walk-off home run that lifted the White Sox to a 7-6 victory over Houston. The Sox took a 2-0 lead in the World Series with the victory Sunday in Chicago.

This one wasn’t as long, but it was just as damaging.

Podsednik lofted the ball to right-center field, and players and fans craned to see whether it would clear the fence. When it did, Chicago players poured out of the dugout to greet Podsednik at the plate.

When the Series resumes Tuesday in Houston, Roy Oswalt pitches for the Astros against Jon Garland.

“Well, we’re not in a good spot,” Houston manager Phil Garner said. “We had a chance to win this ballgame. We have to go home and regroup. We’ll make a series out of this.”

Andy Pettitte had put his hometown team in position for its first World Series win, leaving after six innings with a 4-2 lead built by Lance Berkman’s three RBIs and Morgan Ensberg’s solo homer.

Chicago pressured reliever Dan Wheeler on Juan Uribe’s one-out double and Tadahito Iguchi’s walk, and the White Sox loaded the bases when Jermaine Dye was awarded first base on a 3-2 pitch that umpires ruled hit his hand. Houston disputed the call and replays appeared to show the ball striking his bat.

If it had been ruled a foul ball, the count would have remained full on Dye. But he took first, Qualls relieved and he left his first pitch over the plate. Konerko turned on it and sent it deep into the left-field bleachers.

“I’m not going to tell him I fouled it off,” Dye said. “Just go to first and, hopefully, we get a big hit and we did.”

A week earlier, Konerko was selected MVP of the AL championship series win over the Los Angeles Angels. Two days later, his wife gave birth to their first child, Nicholas.

It was Konerko’s fifth postseason homer and the first Series slam since the Yankees’ Tino Martinez in 1998.

“That was the second-best feeling I’ve had all week,” he said. “Had the baby born, that was first.”

Rain started during batting practice, and it stopped and started throughout the game. The first pitch was delayed 7 minutes – the first rain delay at the beginning of a Series game since 1993 – and Pettitte repeatedly kicked the pitching rubber to knock mud out of his spikes.

It was 45 degrees when the game began, weather more suited to football than baseball. While rain held off in the early going, it began again in the fifth, just before Berkman doubled down the left-field line to break a 2-2 tie. For the rest of the game, many fans wore slickers and held up umbrellas in an attempt to stay dry.

Making his record 34th postseason start, Pettitte needed 54 pitches to get through the first three innings and allowed two runs in the second, but those were the only runs he gave up.

Ensberg led off the second with his first homer since Sept. 20 at Pittsburgh, and gave Houston its first lead of the Series.

Chicago went ahead 2-1 in the bottom of the inning with the help of some odd bounces. Aaron Rowand hit a one-hopper that Ensberg couldn’t come up with at third and bounced into left for a single.

A.J. Pierzynski hit a ball to left that sliced away from Burke, a relatively inexperienced outfielder who didn’t start the opener. While the ball was catchable, it bounced off the wall at Burke’s side, but Pierzynski was held to a single because Rowand went back to tag up and only reached second.

Joe Crede hit an opposite-field bloop single to right on the next pitch for his 10th postseason RBI, sending Pierzynski to third. Uribe popped to short right on the following pitch, and the ball bounced off the glove of second baseman Craig Biggio and dropped. Pierzynski scored on the fielder’s choice as right fielder Jason Lane threw to second for a forceout.

Willy Taveras tripled into the right-field corner in the third and made it 2-2 on Berkman’s sacrifice fly.

Ensberg saved a run in the bottom half when he dived to stop Carl Everett’s two-out grounder with a runner on third. In the fourth, Pettitte pitched Houston’s first 1-2-3 inning of the Series.

Notes: Florida’s Alex Gonzalez hit the previous game-ending Series homer in Game 4 two years ago. … It was the first rain delay at the start of a Series game since Game 3 in 1993 at Philadelphia began 1:12 late. … Commissioner Bud Selig didn’t take his front-row seat until after the first inning.