The Brewers pounded out 11 hits, lessening the blow -- momentarily, at least -- of the likely loss of Gomez for this series, and Braun and Hart further and even further down the line.
The Brewers are 19-2 in their last 21 games against the Cubs at Miller Park, including nine wins in a row. They have won five of six meetings against Chicago this season.
"We got big hits," Roenicke said. "We've been talking about that, that we haven't done that for quite a while, and we're starting to get some big hits from the guys."
The Brewers scored only17 runs in their previous seven games, but got to Cubs starter Edwin Jackson for a five-spot in the fifth inning to turn a 3-1 deficit into a 6-3 lead.
Milwaukee batted around in the fifth, scoring three of their five runs with two out to chase Jackson. Weeks, Caleb Gindl, Jean Segura and Jonathan Lucroy notched RBI hits in the frame.
Weeks started the scoring with an RBI double into the left-center-field gap, scoring Francisco all the way from first base. He then took third on a Jackson wild pitch, and Gindl tied the game with his first Major League RBI, a liner up the middle past a diving Darwin Barney.
Lohse bunted Gindl to second before Norichika Aoki walked to set up a run-scoring double from Segura and a go-ahead, two-run single from Lucroy, putting Milwaukee ahead, 6-3.
Jackson threw 32 pitches in the fifth, leaving after Lucroy's two-out single with six hits and two runs to his name. Jackson, who signed a four-year, $52 million contract this offseason, took the loss to drop to 3-10.
"We just can't control some innings when they start going a little bad, whether it's fastball command," Cubs manager Dale Sveum said. "Tonight, from the get-go, he didn't have much of a fastball. He averaged 92 mph. It's going to be tough for him to pitch with that velocity. It seems like innings get out of control and they turn into big, crooked numbers."
The Brewe''s big offseason signing fared better than Jackson. Lohse, who signed with the Brewers for three years and $33 million, worked around eight Chicago hits in seven innings for his fifth quality start in a row.
After allowing a three-run homer to Nate Schierholtz in the third, Lohse settled down for four straight scoreless frames. The right-hander allowed just three hits after Schierholtz's homer and threw 96 pitches, 70 for strikes to improve to 3-6.
"I had a rough May dealing with elbow and hamstring stuff," said Lohse, referring to two injuries that forced him to skip a start last month. "I feel like it's coming around. We're back doing the things that we consistently do, and it seems like it gives the team a chance every time I go out."
Meanwhile, the Brewers' offense was in the capable hands of Weeks, who dealt with his share of early-season struggles.
Weeks went opposite field for a two-run homer in the sixth, then belted a solo shot in the eighth inning to center field. They were the seventh and eighth home runs of the season, and gave him five this month.
Weeks is hitting .429 in June with five homers and nine RBIs, despite splitting time at second base with Scooter Gennett. He recorded a hit in his 17th straight start and brought his average up to .230, about where it ended last season.
"It's fun," Lohse said of watching Weeks. "That's him. He works hard every day trying to get his stuff right and it's good to see him enjoying the rewards for all the hard work he puts in."
"I've been feeling good for a while, little bit over a month now, probably," Weeks said. "But the biggest thing is when I do get the call, to go out there and do my job. A lot of things you can't control sometimes. When your name is called, you get up and do your job, so that's what I do."
Francisco put the Brewers on the board first with a high, towering solo home run just over the right-field fence. It was his seventh of the year and second with the Brewers.
The win moved the Brewers a game ahead of the Cubs in the NL Central, leaving Chicago alone in last place. Roenicke shied away from his team using motivation to stay out of the division's cellar.
"No, we're not worried about that," he said. "I'm not thinking that we should beat anybody unless we play a good game. I think every game is very important. We just lost a couple to Houston and you can't take these guys lightly.
"We're not battling for last place, we're battling to try and get back in this thing."