CHICAGO -- Marco Scutaro went 3-for-4 and collected a game-winning RBI to lead the San Francisco Giants to a 3-2 victory over the Chicago Cubs on a frigid Saturday at Wrigley Field.
Scutaro, the Giants' second baseman, drove home starting pitcher Madison Bumgarner with a single in the seventh for a 3-0 lead.
San Francisco won for the fifth time in six games and claimed a second victory in the four-game series heading into Sunday's finale.
Bumgarner (3-0) pitched 6 2/3 shutout innings until giving up a two-out pinch hit homer to Dioner Navarro before departing in favor of lefty reliever Dave Affeldt.
Navarro's pinch hit homer was his second in two days.
Cubs' right-hander Jeff Samardzija pitched solid six innings, allowing two runs on seven hits and striking out five, before leaving for reliever Michael Bowden, the second of four Cubs pitchers.
Chicago loaded the bases with one out in the eighth inning, but right-handed reliever Santiago Casilla got Welington Castillo to hit into an inning-ending double play.
Casilla earned the save, his first of the season.
Giants' outfielder Andres Torres doubled to lead off the fifth and scored the game's first run on Gregor Blanco's single to right. Blanco was tagged out to end the inning while trying to stretch the single into a double.
Scutaro singled to center to open the sixth inning, reached second on a wild pitch and came home when Pablo Sandoval also singled to center off Samardzija.
Scutaro picked up his RBI in the seventh with a single that scored Bumgarner, who had reached base on a sacrifice bunt.
Navarro's two-run home run came with Alberto Gonzalez aboard. It was the 110th and last pitch for Bumgarner.
Cub leadoff batters reached base in three of the first four innings and they had runners on second and third with none out and the bases loaded with two out in the second. But Chicago failed to score as Samardzija grounded out to short.
The Giants had a runner in scoring position in the third after Blanco reached on an error and advanced to second on Scutaro's single to center. But Sandoval grounded to third to end the inning.
Weather conditions were clear but challenging on Saturday. Game time temperatures hovered at 38-degrees and winds clocked at 14 mph from the northwest created a wind chill of 29.6 degrees.
NOTES: The Cubs place right-handed closer Kyuji Fujikawa on the 15-day disabled list Saturday, one day after he blew a late lead before the Cubs rallied in the bottom of the ninth for a 4-3 victory. Fujikawa has a strain in his right forearm. He was replaced by Rafael Dolis from Triple-A Iowa, where he had no decisions and a 3.86 ERA. ... The Cubs played errorless baseball for the second straight day but still have a 10 errors for the season, second only to the Angels' 11. ... Starlin Castro's .414 average entering Saturday ranked second in the National League behind Milwaukee's Jean Segura (.429). ... The Giants have posted the second-best record in baseball since last Aug. 1, going 45-25 (.643). Only the Athletics are better (47-23, .671). ... Giants' infielder Brett Pill, on rehab assignment with Triple-A Fresno, has a double, two home runs and four RBIs in six games. He's recovering from right knee surgery. ... Madison Bumgarner might be only 23 and the second-youngest player on the roster, but he's already has made 90 appearances, including 87 starts, through Saturday, ... The four-game series, the Giants' only scheduled trip to Chicago this season, concludes with a 1:20 p.m. game Sunday at Wrigley Field. The Cubs are at AT&T Park for a three-game series late in July.