The surprising Marlins began the day four games behind Cincinnati in the NL wild-card race. Florida, which moved within three games of .500 for the first time since April 15, and Milwaukee play again Monday night.
"This win itself is huge, to get seven in a row," said Jacobs, who had been 0-for-8 as a pinch-hitter this season. "We keep creeping closer to the wild card and .500."
Brewers reliever Brian Shouse (1-1) got two quick outs in the ninth. Hermida then walked and the lefty-hitting Jacobs sliced a line drive through the vacated hole at third, scoring Hermida.
"Right before that pitch, I saw (third baseman) Bell shift over toward the shortstop hole, and it caught my eye," Jacobs said.
"It was a good pitch, a fastball in -- he just inside-outted it," Shouse said.
Left fielder Kevin Mench, who had been shaded toward left-center, had to run to the fence in foul territory to get the ball.
"The ball hugged the wall," said Mench, who briefly bobbled the ball. "By the time I picked it up, he was already rounding (third). I would have had to make a perfect throw home to get him."
Hermida was determined to make it home.
"I told (first-base coach) Perry Hill I was scoring on a double no matter what," he said. "My head was down the whole way and I wasn't stopping for nothing."
Florida's Dan Uggla singled home Hanley Ramirez with the go-ahead run in the eighth inning.
With Florida trailing 2-0, Miguel Cabrera and Josh Willingham led off the seventh with home runs off Chris Capuano.
"I was on top of my game for most of the game," Capuano said. "I lost it for a second, and it was to the two wrong guys."
Bill Hall singled in both Milwaukee runs in the fifth.
Capuano gave up two runs and four hits in six-plus innings. He walked none and struck out nine.
Florida's Anibal Sanchez threw 114 pitches in six innings. He allowed two runs, seven hits, three walks and struck out six.
Cabrera hit his 23rd homer and Willingham followed with his 19th homer, finishing Capuano.
"The way Capuano was dominating with his location, he was making us look not so good," said Willingham, who was 3-for-4. "Then Miguel drives a ball like that, and it kind of lights a fire."
Florida had runners on second and third with one out in the seventh, but reliever Jose Capellan struck out Hermida and pinch-hitter Joe Borchard.
Capuano led off the fifth with a single to center, and he was held up at third when Gabe Gross doubled to deep right-center. Two outs later, Hall lined Sanchez's 3-2 pitch to center.
- Brewers CF Brady Clark (upset stomach) was a late scratch. Gross replaced him.
- Cabrera's 31 RBI in August set a Marlins record for any month. Cabrera (May '06), Gary Sheffield (August '96) and Moises Alou (April '97) all had 30 RBI in a month.
- All six outs in the first innings were strikeouts. Capuano had six strikeouts through two innings.
- Brewers hitters fouled out five times.
- Bell's home run was his third hit of the game and his first homer since being acquired from Philadelphia on July 28.