Derrek Lee hit a grand slam and a three-run homer Thursday night for a career-high seven RBIs, and the Chicago Cubs opened an 11-game homestand by beating the Milwaukee Brewers 9-5.

Lee drove his 10th career grand slam off reliever Chris Smith in the fourth after connecting for a three-run shot off starter Seth McClung in the first. Jake Fox and Geovany Soto also had solo shots off McClung (3-2), who was making just his second start of the season.

Ryan Dempster (5-5) got his first win since May 30 and improved his career record against the Brewers to 10-3. He gave up four runs _ three earned _ and eight hits in 6 2-3 innings, including Mike Cameron's 13th homer in the second and Prince Fielder's 21st in the sixth.

He left after Ryan Braun's RBI single in the seventh, and Jason Kendall's RBI single off Aaron Heilman cut the Chicago lead to 9-5 in the eighth.

Sam Fuld drew a leadoff walk in the first, Ryan Theriot singled and Lee sent his 13th homer deep into the left field bleachers. One out later, Fox hit his third home run of the season to give Dempster an early 4-0 cushion.

After Cameron's two-run drive cut the lead in half, the Cubs drove out McClung with a five-run fourth.

Soto led off with his eighth homer. After a single by Mike Fontenot, a sacrifice and infield single by Fuld, Smith relieved and walked Theriot to load the bases for Lee, who sent another long drive into the left-field bleachers.

McClung gave up seven hits and seven earned runs in 3 1-3 innings.

NOTES: It was Milwaukee's first trip to Wrigley Field this season, even though the teams are in the same division and located only 90 miles apart. ... Cubs 3B Aramis Ramirez (shoulder) and CF Reed Johnson (back) will begin rehab assignments with Class A Peoria this weekend. Ramirez is slated to play three games beginning Friday and Johnson will start Saturday. Both could be activated by the Cubs on Monday. ... Alfonso Soriano, batting only .230, got his second straight game off and has been working with hitting coach Von Joshua.