CHICAGO – Derrek Lee was a member of the Florida Marlins four years ago when they came to Wrigley Field and won the NL championship series. What he heard from the crowd Sunday in the Chicago Cubs’ regular-season finale at home sounded very familiar.

“This is playoff atmosphere already. I remember playing here in ’03 in the playoffs, this is pretty close right now. I’m excited if we are able to get into the playoffs what it will be like,” Lee said.

Lee homered and Carlos Zambrano earned his career-best 17th win to help the Cubs beat the Pittsburgh Pirates 8-0.

The victory, coupled with Milwaukee’s 7-4 loss in Atlanta, pushed Chicago’s lead in the NL Central to 3 1/2 games with six to go – all away from home.

The Cubs, who have won 10 of 12, are off Monday before hitting the road to play Florida and Cincinnati as they try to wrap up their first playoff berth in four years.

The second-place Brewers have seven games left – all at home – against the Cardinals and Padres.

“I felt all along in September we’d get hot and we have,” Chicago manager Lou Piniella said. “We’ve still got some work to do. This is a tough little trip. … I’ll be more excited if and when we clinch. That’s what this is all about. We’re in good position, but again there is baseball to be played.”

Zambrano allowed just three hits in six innings but was forced to leave with cramping in his forearm and legs while warming up for the top of the seventh.

He had doubled and raced home to score in the sixth, and that contributed to his problem. He had a similar bout with heat cramping against the Mets in August and vowed to drink more water.

“I’m a pitcher, not a doctor,” Zambrano said. “But I have to do like a month ago. I had the same thing. I took care of that and now I have to do the same thing and start drinking more Gatorade and whatever. Whatever I have to do to solve the problem.”

A huge cheer went up when the scoreboard showed that Atlanta had scored four runs in the seventh to take the lead against the Brewers, and the crowd began to do the Tomahawk Chop – a ritual at Braves games. The fans did it again when Atlanta tacked on two in the eighth, and for a third time when the final score was posted.

“That was pretty cool,” Lee said.

“I don’t think there is an environment like this in baseball. I really don’t,” Piniella said.

Ronny Cedeno – a late addition to the lineup when regular shortstop Ryan Theriot was scratched with back spasms – also homered as the Cubs sent the Pirates to their ninth straight loss.

“We ran into a buzz saw. It’s that simple,” Pirates manager Jim Tracy said. “They are very focused and on a mission. After today, personally I think they’re going to accomplish it. … Just everything is going right for them.”

Zambrano (17-13) walked three and struck out six, fanning his first four batters.

When he went out to warm up for the seventh, trainer Mark O’Neal came to the mound and moments later Zambrano left, shaking Piniella’s hand near the third-base line. Gametime temperature was a pleasant 72 degrees.

“When I scored I felt something in my leg and when I was warming up I threw two sliders in a row and I felt it in my forearm,” Zambrano said.

Kerry Wood replaced Zambrano and pitched two innings. Michael Wuertz completed the three-hit shutout.

Zambrano has won three of his last four starts – he dropped his previous outing on three days’ rest against the Reds – and will make his final start of the regular season Saturday in Cincinnati.

Tom Gorzelanny (14-9), who was 2-1 with a 0.82 ERA in three career starts against the Cubs, failed for a third straight start to get his 15th victory. And with a career-high 195 2-3 innings, he might not get another chance if his last scheduled start is skipped. He gave up 12 hits and six runs in 5 2-3 innings.

Chicago went ahead in the second when Matt Murton doubled, moved to third on a bloop single by Geovany Soto and scored on Cedeno’s single.

The Cubs made it 3-0 in the fifth when Alfonso Soriano opened with a single, stole second and scored on Lee’s RBI double. Aramis Ramirez was intentionally walked and Murton beat out an infield single to load the bases before Soto delivered a sacrifice fly.

After Mark DeRosa singled in Zambrano, Lee hit a two-run homer just over the wall in right-center, his 20th of the season, to finish Gorzelanny.

Cedeno added a two-run shot off Romulo Sanchez in the seventh.

Notes: Bay, who sat out the first two games of the series, returned to the Pirates’ lineup. He’d been in a 2-for-17 skid in five previous games since missing a week with a sore right knee. … The Cubs’ final home crowd of 41,364 brought the 81-game regular season total to 3,252,462, a franchise record.