CHICAGO — No hard feelings from Casey McGehee. Just some hard shots.

The rookie homered while setting career-highs with four hits and five RBIs to help the Milwaukee Brewers pound Rich Harden and the Chicago Cubs 11-2 Saturday and snap a three-game losing streak.

Mike Cameron and J.J. Hardy also went deep to back a solid effort by Braden Looper (7-4). But McGahee delivered his best performance against the organization that let him go during the offseason.

“I’m still trying to make my way with this organization and this club, be able to contribute and help these guys win,” he said. “So I don’t really have the luxury of thinking about the opponent or who it’s against or where it is.”

Claimed off waivers in October, he made the team in spring training and is now batting .331 in 46 games after going 4-for-5. He singled twice and tripled before hitting a two-run homer off Jeff Samardzija.

The Cubs had won three in a row after going 11-14 in June, but this was simply a brutal afternoon all around — especially for Harden and Alfonso Soriano.

Harden (5-5) allowed seven runs and eight hits over two-plus innings in the shortest start of his career. Soriano, meanwhile, got booed for his flubs in the field and at the plate after being dropped from the leadoff spot to sixth in the order.

And the Brewers simply pounded away.

Shut out twice in the previous six games, they scored five in the first while sending nine batters to the plate. Cameron followed McGehee’s two-run bases-loaded single with a three-run homer.

“I think that I can help the team win,” said McGehee, who appeared in nine games with the Cubs last September. “That might not be with 30 home runs or driving in 120, but I think I can definitely be a contributer on a winning baseball team.”

Hardy hit a solo shot in the second, and after McGehee led off the third with his first career triple, Cameron chased Harden with a line-drive double to left that sailed over Soriano’s head after he initially broke in, drawing more boos.

Besides that mistake, Soriano went 0 for 4 after being dropped from first to sixth in the order and is now hitless in his last 16 at-bats. His groundout with the bases loaded to end the first set the tone, and the boos continued throughout the game.

“It’s part of the game,” Soriano said. “If you get a hit, they want to clap. If you strike out, they want to boo.”

The Cubs also loaded the bases in the second, but did not score until Milton Bradley hit a two-run homer in the third. They did little otherwise against Looper, who gave up six hits in six innings, and three relievers.

“I didn’t think Looper’s stuff was off the charts good,” manager Ken Macha said. “When you’re pitching in this ballpark and the wind is not blowing in, a lot of runs can be scored.”

Harden fell to 1-4 in his last six starts while throwing — in his words — “batting practice.”

For Soriano, it was simply another frustrating day.

“I’m really struggling at home plate, so I don’t know what I have to do,” he said.

Manager Lou Piniella wants Soriano to narrow his stance and “get a little weight on his backside so he can sit on (the pitch) a little longer.”

He’s also going to stick with this lineup for now, with Kosuke Fukudome leading off, and hope Soriano breaks out of his two-month slump. He held out Soriano on Wednesday and Thursday while Sam Fuld batted first and decided to drop him in the order after watching him go 0 for 5 while leading off Friday.

“I think you’ve got to give it more than one day to see how things work or don’t work,” Piniella said. “I know you people want quick results, but that’s too quick.”