Zambrano (12-5, 3.38 ERA) failed to earn a decision in a 6-5 win at Florida on Friday after giving up five runs and five hits while walking five in six innings. It came one game after the All-Star allowed a season-high nine runs over 4 1-3 innings of a 12-3 loss to St. Louis on Aug. 9.

"I've been rushing a little too much and I've been working with the pitching coach on correcting some things in my approach," Zambrano said.

The right-hander has a good chance of bouncing back Thursday as he tries for a fifth straight win over Cincinnati (56-71). Zambrano, 13-9 with a 3.20 ERA in 26 starts versus the Reds, is 3-0 with a 1.17 ERA against them this year and has allowed one run and four hits in 16 innings over his last two starts against Cincinnati.

"We need to get him going the way he can pitch," manager Lou Piniella told the Cubs' official Web site. "You need to have your ace win baseball games for you."

The NL Central-leading Cubs (77-49) hope to rebound after falling 2-1 to the Reds on Wednesday. Chicago, the NL leader with 678 runs, was held to three hits against Bronson Arroyo in losing for the fifth time in its last 22 games overall while falling to 46-18 at home.

"In this ball park you rarely see 2-1," Reds manager Dusty Baker said of a night at Wrigley Field where the wind was blowing in.

Mark DeRosa had two hits and drove in the lone run for Chicago, which holds a five-game lead over Milwaukee in the division. Aramis Ramirez had the Cubs' other hit and is batting .480 (12-for-25) with nine RBIs in his last eight contests. DeRosa, 3-for-8 in the series, is 5-for-7 with two RBIs versus Cincinnati's scheduled starter Josh Fogg.

Originally scheduled to start Friday for Cincinnati, Fogg (2-5, 7.71) was moved up a day after Aaron Harang suffered back spasms. Fogg, who pitched two scoreless innings of relief in a 9-3 loss to St. Louis on Saturday, has an 8.57 ERA in 11 starts this season.

The right-hander allowed four runs and six hits in 4 2-3 innings of a 5-2 loss at Pittsburgh on Aug. 13.

"I didn't make the pitches when I needed to," said Fogg, 0-3 with a 10.19 ERA over his last four starts since beating the New York Mets on July 19.

Fogg is 7-8 with a 6.33 ERA in 21 starts versus Chicago and yielded nine runs in two innings of a 12-3 loss at Wrigley Field on April 16.

Jolbert Cabrera had the game-winning RBI on a sacrifice fly Wednesday for Cincinnati, which had four hits to improve to 6-18 since last winning consecutive contests July 22-23 versus San Diego.

Reds shortstop Jeff Keppinger has hit safely in four straight games and is batting .350 (14-for-40) with five RBIs against Chicago in 2008.