Madison Bumgarner allowed three hits over seven innings, Hector Sanchez hit his first major league home run and the Giants downed the Mets, 7-2, in the nightcap of Monday's doubleheader.
San Francisco won the opener, 6-1, behind five solid innings from Tim Lincecum and home runs from Nate Schierholtz and Buster Posey.
Bumgarner (3-1) was charged with one run, struck out four and walked two for the Giants, who took three of four from the Mets in this series and have won eight of their last 11 overall.
Pablo Sandoval hit a two-run homer in the first inning, Sanchez finished with three RBI and Gregor Blanco knocked in a pair.
Dillon Gee (1-2) gave up seven runs on 12 hits over 6 2/3 innings in the loss, while Daniel Murphy and Justin Turner had an RBI apiece for New York, which has dropped six of its last eight games.
Blanco began the game with a single before Sandoval gave the Giants the early lead with a one-out, upper-deck blast to right. Schierholtz, who had a three- run homer in the opener, followed with a triple and scored on Sanchez's sac fly, making it 3-0.
There were two on and two down in the fourth when Blanco contributed again, lifting a fly ball to deep left, which bounced out of the glove of the diving Jason Bay. Brett Pill and Emmanuel Burriss scored on the play -- which was ruled a double.
The Mets made it 5-1 in the home half when Turner singled David Wright home from second, but Bumgarner didn't allow a hit over the next three innings.
Sanchez followed a Sandoval walk with a two-out homer to right in the seventh and Javier Lopez relieved Bumgarner to start the eighth.
New York quickly took advantage, placing runners at the corners courtesy of Lucas Duda's leadoff double and Ruben Tejada's single. Murphy scored Duda with a sac fly before Sanchez issued consecutive walks to load the bases.
But Jordany Valdespin popped out to the infield against Clay Hensley, and Ike Davis, who twice made the final out with bases loaded in the opener, struck out looking to end the inning.
Sandoval has hit safely in all 16 games this season, which ties the club- record in the San Francisco-era (since 1958) for the longest hit streak to begin a season. He is tied with Hall of Famer Willie Mays...It was Bumgarner's first career start against the Mets.