San Francisco, CA (Sports Network) - Madison Bumgarner took a shutout into the ninth inning against the Chicago Cubs, and the San Francisco Giants survived a late offensive surge to hold on for a 4-3 win in the opener of a four-game series at AT&T Park.

Bumgarner (6-4), winless in his previous four starts, gave up back-to-back singles to Starlin Castro and Joe Mather to begin the ninth.

Santiago Casilla replaced the 22-year-old left-hander and surrendered a home run to Alfonso Soriano.

Bumgarner, who recorded 11 strikeouts and didn't walk a batter, was bidding for his first career complete game and shutout.

A pinch-hitting Bryan LaHair then stroked a one-out double and Casilla appeared to injure himself fielding Darwin Barney's infield chopper. Javier Lopez took over on the mound and Steve Clevenger advanced both runners with a groundout to first. But Lopez earned his first save of the season by retiring pinch-hitter David DeJesus on fly ball to center field.

Ryan Theriot collected three hits, scored twice and knocked in a run for the Giants, who have won four of their last five games.

Paul Maholm (4-4) gave up four runs on eight hits and two walks in 5 1/3 innings for Chicago, which has dropped eight straight on the road.

"I didn't bury some pitches. They did a good job going the other way with two strikes," said Maholm.

The Cubs had broken out of a 12-game skid with a three-game home sweep of San Diego earlier in the week.

San Francisco jumped out to a 2-0 lead in the first inning. Gregor Blanco drew a leadoff walk and scored on a double by Theriot, who moved to third on a Melky Cabrera single before Buster Posey hit a sacrifice fly.

Theriot sparked a two-run third with a leadoff single. Cabrera followed with a triple and scored on a single by Posey.

"We're playing well right now. It's a good vibe in the clubhouse and the dugout," Posey said.

Game Notes

Center fielder Angel Pagan went 1-for-4 to extend his hitting streak at home to 25 games, the longest such streak in Giants franchise history (since 1918)...Bumgarner, who gave up eight hits, improved to 12-2 in his last 15 starts at AT&T Park...The Cubs have lost each of Maholm's last four outings.

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