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San Francisco lefty Barry Zito eyes his first double-digit win season since 2009 this afternoon when the Giants complete a three-game series with the Colorado Rockies at AT&T Park.

Zito improved to 9-8 on the season on Tuesday in St. Louis, as he held the Cardinals to a pair of runs and eight hits in 6 2/3 innings to lower his ERA to 4.19.

"He pitched a great game," Giants manager Bruce Bochy said. "He gave up a couple of home runs ... but he didn't let that faze him at all."

A victory today would give the former AL Cy Young Award winner his first 10- win campaign since going 10-13 three years ago. However, he has lost three consecutive starts at AT&T Park and has a 10.24 ERA in the last two.

Zito tossed a four-hit shutout to beat the Rockies the last time he faced them and is 6-2 lifetime against them with a 2.39 ERA in 18 games (16 starts).

Colorado, meanwhile, will turn to righty Alex White, who is 2-6 with a 5.75 ERA. White struggled with his command on Tuesday against the Los Angeles Dodgers. He only allowed a hit over four scoreless innings, but walked five batters and did not get a decision in his team's 3-1 win.

As part of Colorado's four-man rotation, manager Jim Tracy has tried to limit his starters to 75 pitches.

"We know what we've got. We've got 75 pitches, and our job is to get as far as we can," said White, who has issued at least four walks in four of his past seven starts.

White has lost both of his starts to the Giants and has pitched to an 8.38 ERA in those outings.

On Saturday, Matt Cain tossed 7 1/3 innings of two-run ball and visited the win column for the first time in nearly a month as San Francisco rolled to a 9-3 victory.

Cain (11-5), who had been 2-3 with a 4.40 ERA coming in since his perfect game, fanned six, scattered seven hits and walked one. It was his first win since defeating the Houston Astros on July 15.

"This was the Matt Cain we know," Bochy said.

Buster Posey smacked two hits, including a two-run homer, and Angel Pagan had a two-run triple for Giants, who won for just the second time at home in their last 10 attempts.

"We're going to have to pick it up here at home," Bochy said.

Posey's batting .444 with six homers and 14 RBI in 10 games this month.

Drew Pomeranz (1-7) allowed four runs on six hits with four strikeouts over four frames for Colorado, which had won three of its last four.

"I just made some bad pitches and they put some good swings on my bad pitches," Pomeranz said.

San Francisco is 7-3 against the Rockies this season.