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 pens.
Beltran and Freese each got Bumgarner with two strikes.
"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."
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. He received a nice ovation during pregame introductions. ... 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.
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