The Cardinals will try to earn a season-high sixth consecutive win Thursday night in the first of four games at Miller Park, where the Brewers hope to have Ryan Braun back.
St. Louis (76-63) was tied for the division lead Sunday but heads to Milwaukee with a three-game cushion on the Brewers (73-66), who have lost a season-high eight straight.
Peter Bourjos hit a walk-off single Wednesday to keep the Cardinals' streak going with a 1-0 victory over Pittsburgh.
"We played good baseball (in Pittsburgh), but we have to keep going," catcher Yadier Molina told MLB's official website. "Milwaukee, I know they're not playing well right now, but they are a dangerous team. We have to be ready for them. They're hungry."
Milwaukee endured a 6-2 loss to the Chicago Cubs on Wednesday night and was outscored 17-5 in the three-game sweep to the Central's last-place club. The Brewers have hit .211 and been outscored 55-16 during their longest skid since a nine-game dip May 10-19, 2010.
"I don't understand it," manager Ron Roenicke said. "We haven't pitched well. We haven't played good defense. We haven't been swinging the bat well, either."
Milwaukee played without Carlos Gomez, who could be out until the middle of this month with a sprained left wrist, while Braun was back home awaiting the birth of his first child. Braun's wife was reportedly in labor after Wednesday's loss, but Roenicke was unsure of the slugger's status for Thursday's opener to a season-high, 11-game homestand.
"(Labor) can last a while," Roenicke told MLB's official website. "So we'll see."
The Brewers will play seven games against the Cardinals over the next two weeks and visit St. Louis from Sept. 16-18.
The Cardinals have won seven of 12 meetings this season and took two of three Aug. 1-3 at Busch Stadium. They've also won 12 of their last 16 in Milwaukee and will try to earn another win while adding to Wily Peralta's woes.
The right-hander has given up a combined 14 runs in eight innings in back-to-back defeats after going 6-1 with a 1.59 ERA over the previous seven starts. He was charged with six runs in three innings, his shortest outing this season, in a 13-2 drubbing at San Francisco on Friday.
Peralta (15-9, 3.82 ERA), however, is 4-0 with a 2.16 ERA in his last four starts against St. Louis and has gone 3-0 with a 1.35 ERA in his three matchups this season. He gave up two runs in 6 2-3 innings in his most recent meeting, a 7-4 victory Aug. 1.
Michael Wacha (5-5, 2.79) is expected to return from the disabled list in the start to an eight-game trip. The right-hander hasn't pitched for the Cardinals since a 5-2 win over the New York Mets on June 17 because of a stress reaction in his throwing shoulder.
Wacha did not get a decision in his only start against the Brewers, a 5-3 loss April 28. He gave up three runs in 6 1-3 innings and struck out nine. He's gone winless in his last nine road starts and has dropped five consecutive decisions there since earning a win in relief in an 8-5 victory against Milwaukee on Aug. 19, 2013.
The Cardinals, losers in 10 of 15 on the road, haven't won six in a row overall since the end of last season.