Carlos Beltran connected on two homers and David Freese added a tie-breaking solo home run as St. Louis pounded out a 13-7 win on Saturday in front of 16,098 at Marlins Park.
Despite allowing a career-high seven runs over five innings, Lance Lynn (9-1) picked up the victory, while Tom Koehler (0-5) absorbed his roughest big league outing.
Koehler gave up nine runs on eight hits in 4 2/3 innings.
"Tommy, it was a struggle for him from the start," Marlins manager Mike Redmond said. "It makes it tough on our bullpen when we only get 4 2/3 out of the starter."
The 13 runs and 17 hits allowed by Miami were season highs in both categories.
Offensively, there were encouraging signs, as the team pulled even at 6 in the second inning on Stanton's homer, after trailing by five runs in the first.
Showing some offensive consistency is a change from most of the season, where runs have been hard to come by.
"Earlier, there would have been dead energy in the dugout," Stanton said. "It was good to snap back right away."
The Marlins scored as many as seven runs for the eighth time this year.
"It was a battle from the beginning," Koehler said. "The team did a great job of fighting back today. It's unfortunate that I wasn't able to keep them down when we got back into that game. That's the most disappointing part.
"The team fought back. We had a chance to tie that game up, take the lead. The Cardinals did a great job also of adding on runs. It was a dog fight right from the beginning."
For the Marlins, it was the 13th time in club history a starter gave up exactly nine runs. The last to do so was Ricky Nolasco on June 20, 2012, against the Red Sox.
Nolasco also holds the franchise record for most runs allowed in a game, 11, on Aug. 17, 2011, against the Rockies. Five times in team history have pitchers given up 10 runs.
"What we've talked about since Spring Training is, the key for [Koehler] is to throws strikes and to pound the strike zone," Redmond said. "His first few starts, he was pretty good at throwing strikes and staying aggressive. In his last few, he's gotten behind some hitters. He walked the leadoff guy. And any walk, especially with this lineup, it's going to hurt you."
Miami pitchers combined for 13 strikeouts, with 10 by Jose Fernandez, in Friday's 5-4 win. Fanning 13 times matched the most by the Cardinals this year, and it was a high for a nine-inning game.
On Saturday, the Cardinals came out ready for revenge. And the Marlins' bats also woke up early.
In the first inning alone, the teams combined for nine runs on eight hits. A total of 19 batters came to the plate, and the two starters amassed 64 total pitches.
Koehler walked Jon Jay to open the game. Matt Holliday reached on an infield single with one out, and Allen Craig was plunked by a pitch to load the bases. Yadier Molina slapped a two-run single to left, and Freese added an RBI single to center. Daniel Descalso added a run-scoring double, and the fifth run scored on Pete Kozma's fielder's-choice grounder.
"Right from the beginning, they came out with a vengeance against a scrappy team that is seeing the ball well right now," Cardinals manager Mike Matheny said.
Miami wasted no time chipping back into it, scoring four times off Lynn in the first.
Pierre led off with a triple and Ed Lucas tapped an RBI infield single. Adeiny Hechavarria delivered a two-out RBI single and Brantly added a two-run single.
"I was happy with the way we came back and made it a ballgame after getting down so many runs early," Redmond said. "We watched two starters out there having a tough time, plowing through the lineup."
St. Louis padded its lead to 6-4 when Beltran led off the second inning with a home run to right.
Miami pulled even in the second on Stanton's two-run homer to right-center, estimated at 409 feet. Stanton's fifth shot of the season made it 6-6.
"I'm having good at-bats, swinging at good pitches," said Stanton, who has five hits and four RBIs in the first two games of the series. "I am being ready for every pitch and not taking any pitches off. Not that I do intentionally, but sometimes when you fall out of your rhythm and game plan, that's what happens."