Gallardo won for the first time since beating Houston on Aug. 8, a span of seven starts. He allowed three singles and a double while walking three and striking out six.
He was making his 10th start since coming off the 15-day disabled list with a left oblique strain. Coming in he was 3-3 in that span, including three no-decisions. He had one of his better outings in his last start, a no-decision in an 8-6 loss to St. Louis last Monday. He went seven innings, allowing two runs on four hits.
Gallardo (12-7) said that he simply wasn't locating the fast ball before the game against the Cardinals. Now, he was.
"It's just the ball was up in the zone," Gallardo said of earlier troubles. "The last two I was able to keep the ball down. These are big league hitters. You leave the ball up, it's gonna get hit."
The Brewers 24-year-old right-hander led off the fifth with a double, then scored two outs later when Braun blooped an opposite-field, broken-bat double down the first-base line.
The Cubs had held their opponents scoreless for 25 innings before Braun's hit, a streak that started Sept. 8 against Houston.
Braun came in 1-for-8 in the series against the Cubs, but reached base three times on two singles and shortstop Starlin Castro's throwing error.
"Our pitchers have really thrown the ball well for the last few weeks," Braun said. "It's nice to finally pick somebody up. Yovani threw the ball great. Fortunately, his bat was in the lineup for us."
Cubs manager Mike Quade said there is no margin for error in a close game.
"Often times, something like that will happen. It's unfortunate, but that's just one run," he said. "So, we needed to find a way to score a couple."
Axford stayed on and pitched the ninth for his 21st save in 23 chances, finishing the five-hitter and Brewers' sixth shutout.
Casey McGehee homered in the eighth after the Brewers scored their first run of the three-game series. He hit the first pitch from reliever Thomas Diamond into the Brewers' bullpen in left for his 21st home run. He also snared a hard grounder off the bat of pinch-hitter Aramis Ramirez in the ninth.
Casey Coleman (1-2), the club's 15th round pick in the 2008 June draft took the loss in his fifth career start after relieving in his first four games.
He allowed one run and five hits, struck out three and walked three as he tried to duplicate the Cubs' dominance the previous two games.
The Brewers' offense scratched out just three hits in each loss after producing 20 runs on 30 hits to take two of three from St. Louis as the six-game homestand began.
Quade said that Coleman did a fantastic job despite being matched up against Gallardo.
"The kid battled today, but Gallardo, Gallardo's tough. You've got to give him his due," Quade said.
Coleman showed some veteran composure weathering Castros' throwing error, his 25th, that set up a bases-loaded jam in the third.
Corey Hart walked before Castro bobbled Braun's two-out grounder and then threw wide of first. With Hart at third and Braun at second, Coleman intentionally walked Prince Fielder and then got McGehee to hit into a fielder's choice.
RHP Carlos Silva will not make his scheduled start Tuesday against the Cardinals at St. Louis due to a right elbow strain. Quade said Silva came in during batting practice and told them about the injury. Silva will return to Chicago to be examined Monday. RHP Jeff Samardzija will make start instead. ... Quade said that Ramirez, who missed five consecutive games with a sore right quad, should be ready Monday as the Cubs face the Cardinals. ... With a look toward next season, Macha said that RHP Mark Rogers, the team's top pick in the 2004 first-year player draft, would get a start against the Florida Marlins during the final homestand. ... Fielder's 95 walks leads the NL.