ST. LOUIS -- Stephen Piscotty said after Thursday night's game that it's fun to be part of an offense like the St. Louis Cardinals'.

It's a pretty safe bet that St. Louis wouldn't be having as much fun the last two months without Piscotty's immense contributions.

The rookie first baseman/outfielder was at it again in the opener of a four-game series with the Milwaukee Brewers, knocking in his team's last four runs in a 7-3 verdict at Busch Stadium.

After following a game-tying three-run homer by shortstop Jhonny Peralta in the bottom of the fourth with a solo blast over the Milwaukee bullpen in left-center field, Piscotty added a bases-loaded two-run single in the fifth and then tacked on a two-out RBI single in the seventh.

In his first 58 big league games, Piscotty is batting .313 with six homers and 37 RBIs. His latest performance enabled the Cardinals (97-56) to maintain their four-game lead over Pittsburgh in the National League Central and cut their magic number for a third straight division title to six.

"That was definitely one of the better ones," Piscotty said of his 3-for-4 outing. "I've never been part of back-to-back homers before. The stadium was just rocking. It was a fun night all the way around."

It didn't start out as much fun for St. Louis as the Brewers (64-89) touched starter Michael Wacha for three first inning runs, getting an RBI single from left fielder Jason Rogers and a two-run double from third baseman Hernan Perez.

With Milwaukee starter Taylor Jungmann sailing through the first three innings on just one hit and one walk while fanning four, the Cardinals appeared to be in danger of losing a game off their division lead.

But Jungmann's second pass through the order didn't go quite as well as the first.

A leadoff walk to center fielder Tommy Pham and a single by right fielder Jason Heyward set the stage for Peralta's 17th homer, a 403-foot shot into the front row in deep left-center.

It was Peralta's first homer since Aug. 1, when he took Colorado's Jorge De La Rosa deep in a 6-2 loss.

"I've been waiting for that one for a long time," Peralta said. "It's a good feeling, too, to get that one with two guys on base."

Piscotty's clout two pitches later put St. Louis ahead to stay and made a winner of starter Michael Wacha (17-6), who lasted five innings, allowing six hits and three runs with three walks and one strikeout.

After laboring through the first two innings on 56 pitches, Wacha was much more efficient in the last three innings, mixing in more off-speed pitches to help him find a rhythm.

"He just wasn't in sync the first inning," Cardinals manager Mike Matheny said of Wacha. "He'd miss low and then he'd miss high out of the zone. But what was more impressive was that after two innings and almost 60 pitches, he figured it out and then had three clean innings."

Jungmann (9-7) gave up six hits and six runs in his five-inning stint, walking three and fanning five.

"Giving up home runs is frustrating, because it's not something I normally do," he said. "Home runs can change a game quickly and I'm not used to that happening."

Brewers manager Craig Counsell said Jungmann had good stuff but made unusual mistakes, such as the leadoff walk to Pham and the Peralta homer.

"If he makes pitches, he's out of those innings," Counsell said of Jungmann. "You've got to make pitches."

NOTES: St. Louis LF Matt Holliday, who started Wednesday for the first time since suffering a right quad injury July 29, wasn't in the Thursday night lineup. But manager Mike Matheny said it was a scheduled day off and that Holliday came through the game in good shape. ... Milwaukee has replaced RHP Wily Peralta (right oblique tightness), who has been shut down for the season, with RHP Tyler Wagner for Saturday night's game. Wagner pitched in one game earlier this year for the Brewers, taking a no-decision on May 31. ... The Cardinals' 53 home wins entering this game mark the fifth time in six years they've won 50 or more games at Busch Stadium.