From Comcast SportsNetSAN FRANCISCO (AP) -- Ahead by a lot or behind by a bunch, these St. Louis Cardinals are winning every which way.Boosted by two-run homers from proven postseason stars Carlos Beltran and David Freese, and 5 1-3 innings from a steady bullpen, these wild, wild-card Cardinals beat the San Francisco Giants 6-4 on Sunday night in Game 1 of the NL championship series.The defending World Series champions built an early 6-0 cushion and held on. Only two nights earlier, the Cardinals came back from the same deficit, using a four-run rally in the ninth inning at Washington in the deciding Game 5 of the division series."I'm thinking about the D.C. game," Freese said. "They were up 6-0. We were up 6-0. And that shows that you've got to keep playing. ... We were fortunate enough that our bullpen came in and closed the door the rest of the way."Starter Lance Lynn was done after 3 2-3 innings. Edward Mujica, the fifth St. Louis pitcher, struck out the side in order in the seventh for the win. Jason Motte finished for his second save of the postseason.The Cardinals gave first-year manager Mike Matheny a win against his former club.Matheny's crew hardly looked road weary after a cross-country trip. The Giants dropped to 0-3 at home so far during these playoffs, outscored 20-6 at AT&T Park.Game 2 in the best-of-seven series is Monday night. Chris Carpenter pitches for the Cardinals against Ryan Vogelsong.This is the first time the previous two World Series winners are facing off in the postseason since the 1958 World Series between the Braves and Yankees."The way we play the game, we have been in this type of situation before in the regular season," Beltran said. "These guys have this mentality of not panicking."Beltran's fourth-inning drive into the seats in left-center chased San Francisco starter Madison Bumgarner, who has been a far cry from the impressive pitcher he was during the 2010 World Series run.It was Beltran's 14th career postseason home run and third this October."Right now I'm really enjoying myself," Beltran said. "Right now I'm seeing the ball well. I feel like I have a good approach at the plate, I feel like I'm not trying to do too much, and good things are happening."Beltran spent the second half of the 2011 season with San Francisco after a trade from the Mets, but the Giants missed the playoffs last fall a year after the capturing an improbable championship. The orange towel-waving sellout crowd of 42,534 let him have it with boos at every opportunity -- during pregame introductions and each time he stepped into the batter's box.Both teams were well rested a day after a rough night of travel. The Giants barely beat the Cardinals to the Bay Area early Saturday after they were delayed three hours on the tarmac in Cincinnati on Friday night -- to refuel and for a mechanical problem after waiting out the Cardinals-Nationals game to know where they were headed next.Matheny stuck with the same winning lineup that he sent out for Game 5, and some of the same faces came through again."They put together some better at-bats than us," Giants center fielder Angel Pagan said. "They hit some homers and were up 6-0. That's a pretty good lead in the playoffs. We tried to battle back. We did our best but it wasn't our night."Daniel Descalso, who hit a tying, two-out single in Friday's 9-7 win, added two more hits.Descalso hit a one-out double in the fourth, then rookie Pete Kozma drove him home with a double of his own. In the ninth inning Friday, Kozma followed Descalso with a go-ahead, two-run single.Descalso did well playing in his native Northern California. He spends his offseasons in San Francisco's Marina district.Beltran and Freese each had two strikes when they homered."I think that's been very much of a strong suit for us all season," Matheny said. "And it's a beautiful thing when these guys trust themselves when they get to two strikes. They can be a little more selective early in the count and then they're not going to panic when we do get to two strikes. I give the guys a lot of credit."St. Louis 18-game winner Lynn didn't allow a hit until Marco Scutaro's single to left leading off the fourth. Hunter Pence singled two outs later and Brandon Belt drove him home with a single. Gregor Blanco followed with a two-run triple, then Brandon Crawford hit an RBI double. Pinch hitter Aubrey Huff -- a 2010 postseason star now in a diminished role -- drew a walk to cheers of "Aubrey! Aubrey!"And, just like that, Lynn was done."The bullpen did a great job," catcher Yadier Molina said. "We struck first, and to hold that lead, we won with the bullpen."Bumgarner and Lynn each lasted only 3 2-3 innings. That made for a long night in both bullpens.The pressure is now on for the Giants not to fall behind 2-0 at home again. They lost the first two games of their division series here to the Reds last weekend before winning three in a row at Cincinnati. They went 48-33 at AT&T Park this season."We've shown how resilient we can be," manager Bruce Bochy said. "We hate to lose them at home, but it happens. And we've got to wash this one off and come out and be ready to go tomorrow."Bumgarner, a 16-game winner for the NL West champs, lost Game 2 of the division series at home to the Reds exactly a week earlier.He pitched a 1-2-3 first on Sunday but ran into trouble in the second when Molina singled on an 0-2 pitch with one out. Freese then drove a 3-2 pitch over the wall in left-center to give the Cardinals a 2-0 lead.Bumgarner needed 30 pitches to get through the second, and now has an 11.25 ERA in his two postseason starts this year.Lynn returned to the rotation for the NLCS and his first career postseason start after making four relief appearances in the division series. Matheny needed another starter after left-hander Jaime Garcia injured his left shoulder in Game 2 against the Nationals."Right now we feel like everyone's feeding off each other," reliever Joe Kelly said. "If one guy does something, you want to go out and match it and try to keep that momentum going. It shows the confidence that Mike has in this bullpen. It makes us want to play better for him. He hands the ball off and he knows what he's doing."NOTES:Matheny caught for the Giants in 2005-06. ... Freese's two RBIs gave him 25 for his postseason career, tied with Molina for third most on the Cardinals. Albert Pujols is No. 1 with 52 and Jim Edmonds has 41. ... Both teams kept their rosters intact from the division series. ... The clubs split their season series 3-all. ... Giants assistant batting coach Joe Lefebvre took over 1B coaching duties in place of Roberto Kelly, who sustained a concussion after being hit by a ball off Buster Posey's bat during batting practice Saturday. ... Matheny received a nice ovation during pregame introductions. ... More fans packed the viewing portwalk outside the ballpark beneath the right-field arcade.