Chicago (74-47) has the best home record in the NL at 45-17, but entered the second half of the season without a series win on the road since June. But buoyed by their sweep of the Milwaukee Brewers - their closest pursuers in the NL Central - last month, the Cubs maintained their momentum outside Wrigley Field by sweeping the Braves and building a 4 1/2-game lead atop the division following Thursday's 11-7 victory.

"I knew all along that for us to spurt, we needed to play better on the road," said Cubs manager Lou Piniella, whose team outscored the Braves 29-9 in the series. "We needed to put more runs on the board, and that's exactly what we have done."

Alfonso Soriano homered and is hitting .352 (25-for-71) with six homers and 15 RBIs in helping the Cubs, who are 29-30 on the road, win 13 of their last 16 overall.

The eight-game road winning streak is Chicago's longest since reeling off 12 in a row in 1945.

A change of venue may help Cubs staff ace Carlos Zambrano (12-5, 3.22 ERA) as he tries to bounce back from his worst start of the season. The right-hander was tagged for a season-worst nine runs - giving up four home runs - in 4 1-3 innings Saturday in a 12-3 rout by the St. Louis Cardinals at Wrigley.

"His location wasn't good at all," Piniella said. "That's the hardest I've seen 'Z' get hit in the last two years I've been here. I thought he'd throw the ball better. ... But it happens to anybody. The Cardinals are a good hitting team."

Zambrano is 6-4 with a 3.38 ERA on the road, where he has won two of his last three starts. He improved to 4-1 lifetime against the Marlins on July 24, giving up two runs in seven innings of a 6-3 victory.

Florida (63-59) is still locked in a three-team fight with the New York Mets and Philadelphia in the NL East, but is trying to regroup after dropping three of four games to St. Louis. The Marlins failed to salvage a split of the series in Thursday's 3-0 loss - the third time in the last nine games they have been shut out.

"It's just a funk," Florida manager Fredi Gonzalez insisted despite his team losing six of its last nine. "We believe in these guys. I believe in these guys."

Marlins pitcher Josh Johnson (3-0, 3.19) looks to win his fourth consecutive start as he continues to round into form. The right-hander has made six starts since missing the first three-plus months of the season recovering from elbow surgery and has recorded two straight quality outings.

Johnson lasted a season-high seven innings Sunday, limiting the New York Mets to two runs and five hits in an 8-2 victory.

"He's been the stopper for us ever since he's been back," Marlins outfielder Luis Gonzalez said of Johnson. "He hasn't disappointed us."

He did not have a decision versus the Cubs at Wrigley on July 25, giving up two runs - both on solo homers - in 5 1-3 innings while striking out eight in Florida's 3-2 victory.

The Marlins are batting .238 in August, scoring just 44 runs and hitting eight homers in 13 games.