Despite not having his best command, Peralta still just gave up three runs on eight hits in seven innings. He struck out six.
"If he's not going to be sharp and that's what he does, it's pretty good," manager Ron Roenicke said.
Having Ryan Braun and Jean Segura could have helped, but both Milwaukee stars missed the game with injuries.
Braun sat with a slight chest muscle strain, while Segura had a partially closed right eye and bruised right cheek after being accidentally hit during a practice swing by Braun on Saturday.
Segura said after the game he hoped to return this week during the Brewers' seven-game road trip to St. Louis and Cincinnati. Braun might miss three to five days.
The remaining Brewers were overmatched by Hammel, who stayed low and away from the Brewers' remaining potent right-handed bats. Hammel was lifted after allowing pinch hitter Rickie Weeks' single to lead off the bottom of the eighth. Pedro Strop and Hector Rondon held the Brewers hitless the final two innings.
Notes: Despite the win, the Cubs lost the three-game series to the Brewers and extended the team's string of winless series to 13 dating to last season. Chicago last won a series after taking two of three from Cincinnati in September. ... C John Baker went 2 for 4 that ended an 0-for-18 stretch. ... Ron Roenicke said the club would hold off on making any roster moves while Braun and Segura continue to be evaluated. ... The Brewers travel to St. Louis to start a seven-game road trip, with Yovani Gallardo (2-0) getting the start Monday. Chicago begins a three-game set in Cincinnati and sends Jeff Samardzija (0-2) to the mound.
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