Though San Francisco has a better chance of catching the NL West leaders than the Chicago Cubs for the second wild-card spot, Madison Bumgarner should give the Giants a strong opportunity to further cut into the North Siders' lead in the latter.

Looking for a fifth straight winning start, Bumgarner tries to help the Giants hand the Cubs their first losing road series in almost two months Thursday.

By evening the three-game set with Wednesday's 4-2 victory, San Francisco (67-59) snapped Chicago's six-game winning streak and moved within 6 1/2 games of the Cubs for that final wild-card position.

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"We weren't going to win them all," said Chicago manager Joe Maddon, whose club will try to avoid losing its first road series since June 26-28 at St. Louis after falling for the fifth time in the last 26 games overall.

While catching the Cubs (73-52) might be difficult regardless of Thursday's result, a 15th win in the last 18 at home could possibly cut the Giants' deficit behind the division-leading Los Angeles Dodgers to 1 1/2 games.

They should feel confident behind Bumgarner (15-6, 3.02 ERA), who concluded July by allowing six runs in seven innings of a 6-3 loss at Texas but is 4-0 with a 1.42 ERA - and 41 strikeouts to two walks - this month. Though he last faced the Cubs at home in 2013, Bumgarner is 2-0 with an 0.75 ERA in his last three against them at AT&T Park.

''I don't care if I get the win, if we get the win when I start I feel the same way everybody feels,'' said Bumgarner, who admitted he wasn't that sharp while giving up three runs in 6 1-3 innings of Friday's 6-4 victory at Pittsburgh. "You've got to win every game you can win.''

In this last seven starts, the left-hander has yielded two home runs - one fewer than he's hit during that stretch.

"I'm just trying to be aggressive," said Bumgarner, whose five homers are the most in a season by a pitcher since the Cubs' Carlos Zambrano hit six in 2006. "Just trying to do something. Anything productive."

He's never homered in 20 plate appearances while facing Chicago but could have a decent chance to go deep against Dan Haren (8-8, 3.76), who has allowed an NL-high 28 home runs. He's given up seven while going 1-1 with a 6.05 ERA and failing to complete more than 5 1-3 innings in four starts since joining the Cubs at the trade deadline.

His shortest outing with Chicago came Saturday when he lasted 4 1-3 and gave up four runs in a 9-7 victory over Atlanta.

"Obviously, I'd like to do better, be out there longer and stuff like that," Haren told MLB's official website."

He's 1-0 with a 3.55 ERA in two starts against the Giants this season.

Marlon Byrd is batting .424 with three homers and five doubles in 33 at-bats against Haren while Brandon Belt is 4 for 11 with two doubles and a homer. Belt is hitting .391 with 14 RBIs in his last 19 home contests.

It's possible Giants All-Star shortstop Brandon Crawford could sit a second straight game due to tightness in his side. Outfielder Angel Pagan (tendinitis), meanwhile, might be activated from the disabled list.

Chicago's Anthony Rizzo is 2 for 10 with four strikeouts when facing Bumgarner, but Starlin Castro is batting .417 against him.