Maddux gave up four hits over eight scoreless innings with no walks and four strikeouts. His 318th career victory tied Maddux with Phil Niekro for 15th on the all-time list. Ryan Dempster earned his 29th save.
Milwaukee was trying for its second three-game sweep of the Cubs at home this season. Geoff Jenkins, Bill Hall, Russell Branyan and Damian Miller each had one hit for the Brewers, who have lost four of six.
Loser Rick Helling dropped to 2-1.
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