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The San Francisco Giants have already taken the first two games of their series with the rival Los Angeles Dodgers and now have the luxury of turning to their staff ace on Wednesday night.

Matt Cain tries to pitch the first-place Giants to their first three-game sweep in Los Angeles since 2007 and increase their lead over the Dodgers in the NL West.

Cain has won back-to-back starts since going four outings without a win and is coming off Friday's 10-1 victory over the San Diego Padres. He allowed just the one run on four hits over eight innings, striking out six without a walk to move to 12-5 with a 2.90 earned run average in 24 starts this season.

"That's always going to be a plus when the guys put up a big lead like that," said Cain, who contributed with an RBI single. "We have a great team and we have a good group of guys. It's just a matter of us putting it together."

The 27-year-old righty has put it together at times versus the Dodgers, but hasn't been rewarded with wins. He holds a 3.58 ERA in 20 encounters, but just a 3-8 record. Cain did not factor into a 5-3 loss on July 27 after giving up three runs over seven innings in his only other start versus them this year.

San Francisco pushed its lead over Los Angeles to 1 1/2 games with Tuesday's 4-1 victory. Buster Posey knocked in a pair of runs, while Tim Lincecum and the Giants bullpen shut down the Dodgers.

Lincecum gave up just one run on five hits and one walk over 5 2/3 innings for the Giants, who have won four of their last five and seven of 10. Angel Pagan went 3-for-5 with a run scored and an RBI and threw a runner out at the plate to prevent a big sixth inning for Los Angeles.

"It's great to come in here and take the first two games," Giants manager Bruce Bochy said.

One night after Madison Bumgarner outdueled Clayton Kershaw in the Giants' 2-1 series-opening win, Lincecum showed he still has the arsenal that made him a two-time Cy Young Award winner by retiring the first 10 batters he faced.

He ran into trouble in the sixth, but Pagan bailed him out when he threw out A.J. Ellis trying to score from second on Shane Victorino's base hit to center. The Dodgers later loaded the bases and only pushed one run across on Matt Kemp's sacrifice fly.

"We had chances, but couldn't get the big hit," Dodgers manager Don Mattingly said.

Joe Blanton suffered a third straight loss in a Dodgers uniform, allowing four runs on 10 hits and two walks in 5 2/3 innings.

Los Angeles has lost two straight and four of its last six. It hasn't been swept at home in three games by the Giants since April 24-26, 2007. Mattingly hopes that left-hander Chris Capuano can prevent that from happening on Wednesday.

Capuano snapped a three-start slide with a victory over the Miami Marlins on Aug. 12, hurling eight scoreless innings and striking out 10. He was decent on Friday against the Atlanta Braves, giving up three runs on five hits over 7 1/3 frames with eight strikeouts, and did not factor into a 4-3 defeat.

Capuano, who turned 34 on Sunday, is 11-8 with a 3.14 ERA in 25 starts this season to match his win total from a season ago with the New York Mets. A victory in this start would give him his highest single-season total since posting a career-high 18 victories in 2005.

He is just 1-5 with a 5.00 ERA lifetime versus the Giants, however.