One hit, his 20th homer, a solo shot, gave Cincinnati an 8-4 lead in the seventh.
Paul Janish had two hits and two RBI.
Drew Stubbs had two hits and one RBI, while Scott Rolen hit a two-run single for the Reds, who have won four in a row.
Winner Justin Lehr (3-1) yielded five runs and seven hits in 7 2/3 innings with three walks and seven strikeouts.
Closer Francisco Cordero earned his 28th save.
Milwaukee's Prince Fielder hit a three-run homer; Mike Cameron, a solo shot.
Cameron had two hits and two RBI for the Brewers, who blew an early 4-0 lead and have lost four of five.
Losing pitcher Dave Bush gave up five runs on four hits with three walks in 4 2/3 innings.
Copyright 2009 by United Press International.