SAN FRANCISCO — Kelby Tomlinson hit a grand slam for his first career home run and Marlon Byrd added a three-run shot, leading Madison Bumgarner and the San Francisco Giants over the Chicago Cubs 9-1 on Thursday.
The win moved the Giants within 5½ games of the Cubs for the second NL wild-card spot.
Bumgarner (16-6) struck out 12 in six innings, giving up one run and two hits. He won his fifth straight start and matched the Cubs' Jake Arrieta for most victories in the majors.
Tomlinson homered off James Russell in the eighth and received a standing ovation from the sellout crowd when he took his position at second base in the ninth. Matt Duffy and Juan Perez also drove in runs for the Giants, who won their second straight but are 3-5 over their past eight games.
The Cubs lost a road series for the first since being swept by St. Louis in late June. They had won or split their previous six road series.
Dan Haren (8-9) lasted 6 1-3 innings, his longest outing since going seven against Toronto on June 9, a span of 15 starts.
Haren gave up five runs and six hits. He walked three and struck out four.
Starlin Castro doubled home Anthony Rizzo in the second for Chicago.
Bumgarner did not give up a hit after Castro's double, retiring 15 of the final 17 batters he faced.
Perez's second-inning double tied it and Duffy's third-inning single gave the Giants a 2-1 edge.
Byrd's second home run for the Giants, a line drive that just cleared the center field fence, was his fourth in 35 at-bats against Haren.
Cubs: OF Dexter Fowler was out of the starting lineup for a second straight day because of a left shin contusion from fouling a ball off his leg. ... Kyle Schwarber was behind the plate for the first time since Aug. 6 with catcher David Ross on the family emergency leave list.
Giants: SS Brandon Crawford was out of the starting lineup a second straight day with tightness in his left side.
Cubs: RHP Jason Hammel (7-5, 3.35) opens the series against the Dodgers in Los Angeles on Friday night. He's 2-4 with a 4.96 ERA in 11 starts against them.
Giants: RHP Mike Leake (9-6, 3.44) will start Friday night's series opener at home against St. Louis. He's 1-1 with a 1.13 ERA against the Cardinals this season.