NL Central-leading Chicago (70-46) has been getting outstanding pitching from Zambrano (12-4, 2.76 ERA), helping it open a seven-game lead over third-place St. Louis (64-54). He has a major league-leading 1.79 ERA since the start of July, going 4-1 in six starts after coming off the disabled list with a shoulder strain.

The veteran right-hander's last outing was at home, where he is 6-0 with a 2.25 ERA in 12 starts this season. He gave up two runs - one earned - and three hits in five innings against Pittsburgh on Sunday, but did not receive a decision as Chicago won 8-5.

Zambrano's run began against the Cardinals on July 4, when he allowed four hits while striking out five in six shutout innings to lead the Cubs to a 2-1 win. It was his fourth straight win over St. Louis, posting a 1.32 ERA during that stretch.

Zambrano has also won eight straight decisions versus the Cardinals, giving up two earned runs or less in 11 starts over that span. Overall, he is 9-4 with a 2.26 ERA in 19 starts and one relief appearance against them.

Some of Zambrano's success against the Cardinals has been due to his ability to keep Albert Pujols in check. The St. Louis slugger is batting .240 (12-for-50) with 10 strikeouts against Zambrano.

Zambrano, meanwhile, remains one of the majors' top hitting pitchers, batting .429 (15-for-35) with a home run, a triple, two doubles and eight RBIs in his last 13 games.

Chicago struggled at the plate Friday, but managed to beat St. Louis 3-2 in 11 innings. Henry Blanco singled home the winning run with the bases loaded as the Cubs improved to an NL-best 44-16 at home, matching their victory total from last season.

"That's why we call it a team. At some point in the season all 25 count," Blanco said. "I know what my job is. I just got to stay ready when they need me."

After scoring 22 runs in consecutive wins over Houston, Chicago left nine runners on base in the series' opener.

Cubs center fielder Jim Edmonds, though, hit a pair of solo homers against his former team. He was 0-for-7 this season against St. Louis before his second-inning homer.

"It's a little odd to play against a group of individuals that I've been so close to for so long, it's like playing in the backyard with your family. So it's different that way," Edmonds said. "But you know, you got to separate and move on."

Edmonds is hitless in four at-bats against Todd Wellemeyer (8-4, 4.01), who will take the mound for the Cardinals on Friday. Wellemeyer is 1-1 with a 4.09 ERA in two starts and one relief appearance lifetime against Chicago.

In his last outing, the right-hander allowed one run and four hits in six innings as St. Louis lost 5-4 to Philadelphia on Sunday night.

Wellemeyer has not received a decision in his last three starts despite posting a 2.65 ERA, getting seven runs to work with in that span. Cardinals pitchers has gotten little run support over the last two games, with St. Louis crossing the plate three times en route to a pair of losses.

Cardinals third baseman Troy Glaus went 0-for-5 Friday, and is hitless in 29 at-bats while striking out 12 times against the Cubs this season.