Updated

Matt Cain will try to pitch San Francisco to a series victory this afternoon as the NL West-leading Giants play the rubber match of a three-game series with the Chicago Cubs.

Cain had won three straight starts before not getting a decision in a 3-2 win at the Houston Astros on Tuesday. The right-hander allowed two runs on six hits and three walks over 7 1/3 innings, but nearly took a loss before the Giants scored twice in the ninth inning.

Instead, Cain remained at 13-5 on the season with a 2.82 earned run average through 26 starts.

The 27-year-old was excellent against the Cubs on June 2, giving up a run over eight innings while striking out seven. Cain improved to 6-2 lifetime versus Chicago with a 2.06 ERA in 12 starts.

Opposing Cain will be Cubs left-hander Travis Wood, who tries to avoid a ninth straight losing decision and earn his first win since July 6.

Wood dropped his third start in a row on Tuesday versus the Milwaukee Brewers despite going at least seven innings for the third time in his last four appearances. He yielded three runs on five hits in a 4-1 loss, dropping to 4-11 with a 4.71 ERA in 19 starts this year, 11 of those quality outings.

The 25-year-old lefty would love to snap his drought with a first career victory over the Giants. He nearly had it back on June 3, but instead suffered a tough-luck 2-0 defeat after yielding a run over seven innings with seven strikeouts. That left Wood 0-2 with a 4.74 ERA in three career meetings with San Francisco.

After losing Friday's opener, the Giants bounced back with their ninth victory in 12 games by downing the Cubs 5-2. Xavier Nady highlighted a big first inning with a three-run double and Tim Lincecum allowed two runs over 6 1/3 solid innings.

Nady was making his Giants debut after having his contract purchased from Triple-A Fresno prior to the game and he helped the Giants maintain a 4 1/2- game edge over the Los Angeles Dodgers for first place in the division.

"We know what's at stake and we know it's coming down to crunch time," Lincecum said after striking out seven with three walks.

David DeJesus hit a two-run homer for the Cubs, who were aiming to win three in a row for the first time since July 28-30. Justin Germano allowed five runs on six hits over five innings.

The Cubs, though, were limited to just five hits as they were kept off-balance by Lincecum.

"He knows how to get through lineups with his offspeed stuff and his change-up and curveball," Cubs manager Dale Sveum said of Lincecum. "It's not the same Cy Young stuff that we all remember him from."

The Giants defeated the Cubs for the sixth time in the last seven meetings, including a four-game sweep at home from June 1-4.