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Pick your weapon and march 10 paces because the wild, wild National League West could be unofficially decided by this weekend.

After a month of heading in opposite directions, the Arizona Diamondbacks have a chance to bury the San Francisco Giants in the division standings, a feat they can start tonight with a 10th straight victory in the opener of a three- game series.

These two rivals also began the month of August with a meeting in San Francisco, with the Diamondbacks taking two of three after losing seven of the first nine matchups this season. That series victory seemed to spark Arizona, which went 19-10 in August while concluding the month on its longest winning streak of the season.

The Giants, meanwhile, went just 11-18 in the month to drop the defending World Series champions six games back of the first-place Diamondbacks. San Francisco is also 9 1/2 games off the pace in the wild card race.

A series victory this weekend by the Diamondbacks won't clinch them any sort of playoff spot, but it will certainly put them in the driver's seat ahead of the final meeting between the club's this season; Sept. 23-25 in Arizona.

"It's never easy, but we're ready," said Arizona manager Kirk Gibson about the impending series with the Giants.

Arizona certainly has momentum in its favor as San Francisco plated just 77 runs last month and shook up its roster before Wednesday's game with the Cubs by designating both Miguel Tejada and outfielder Aaron Rowand for assignment. Those moves seemed to signal that the Giants are ready to give some younger players a look should they fall further back in the playoff race, but that doesn't make this series any less important.

"I don't see how it couldn't be," said Giants outfielder Pat Burrell, who was activated from the disabled list on Wednesday, on the Giants' website. "There's no secret these guys are coming in [hot]. They've proven that they deserve to be where they're at, and we've slipped -- no doubt about it. But it isn't over. We're going to fight this thing out. The better team is going to prevail, obviously, and obviously we feel like we are that team."

San Francisco's new look paid off on Wednesday as it avoided a three-game sweep with a 4-0 victory. Jeff Keppinger had three hits and both he and Pablo Sandoval hit homers to back eight solid innings from Madison Bumgarner, who matched his career high by striking out 11 batters over eight scoreless innings.

The Giants snapped a three-game slide overall.

"Well, we're not as good as when I first got here. We were three games back and now we're behind further and it's not a good feeling," said Keppinger, who was acquired from Houston on July 19. "This is as close as I've ever been so it's not over by any means. We have a lot of games left and things can change."

One thing that will change for the Diamondbacks is the location of their games. They wrapped up a perfect six-game homestand on Wednesday with a 4-2 win over the Rockies, stretching their home winning streak to a franchise- record 12 straight games.

Miguel Montero hit his second three-run homer in as many games to pace the 4-2 victory and ran his career high hitting streak to 10 consecutive games.

Joe Saunders takes the hill for the Diamondbacks tonight in the search of his first ever win against the Giants. He has lost both of his career outings against them, with each coming this year, while allowing eight runs over 13 2/3 innings.

The 30-year-old southpaw won for the first time in five starts on Saturday, holding the Padres to one unearned run over seven innings while working around four hits and a walk. He improved to 9-11 with a 3.82 earned run average on the season.

Matt Cain goes for the Giants and he struggled in a loss to the Diamondbacks when he last faced them on Aug. 1. The righty was charged with five runs over 5 2/3 innings, ending his five-decision win streak versus the club that included a victory in each of his first three starts against them this year.

Cain, who is 9-5 with a 3.52 ERA in his career versus Arizona, hasn't factored into the decision of his past two starts despite allowing five earned runs over 15 innings. He yielded a pair of runs on five hits over eight frames versus the Astros on Sunday, striking out six in his club's eventual 4-3 loss.

The 26-year-old is 10-9 with a 2.87 ERA in 28 starts this season.