CHICAGO(AP) Ryan Dempster isn't ready to shut it down.

Dempster pitched a five-hitter for his third career shutout, Jeff Baker had a two-run double and the Chicago Cubs beat the Pittsburgh Pirates 6-0 on Tuesday night.

Derrek Lee added a two-run single for the Cubs, who have won seven of nine but were eliminated from the playoff race when the Colorado Rockies beat Milwaukee later Tuesday.

The Cubs (82-74) guaranteed a winning record for the third straight season. It's only the second time in the last 70 years the Cubs have had three or more consecutive winning seasons.

Dempster struck out six and walked two. He retired the ninth inning in order to record his first shutout since July 3, 2001, against the Montreal Expos, when he was a member of the Florida Marlins .

''It's unfortunate the season is coming to an end because I feel stronger than I did earlier in the year,'' Dempster said.

With the victory, Dempster (11-8) became the second active pitcher with at least 87 wins and 87 saves. John Smoltz has 213 wins and 154 saves.

Dempster is 5-1 in his last six decisions and makes his last start Sunday against the Diamondbacks. Cubs manager Lou Piniella believes Dempster is benefiting from the time he spent on the disabled list in July with a broken toe.

''He's gotten better and better as the year worn down. He really has,'' Piniella said. ''He's pitching basically like the way he did last year. I thought he would have a nice strong finish because when he hurt his toe he (the disabled list time) really freshen up his arm.''

Dempster has not allowed an earned run in his last 26 innings at Wrigley Field and his recent performance resembles his 17-6 season in 2008.

''Tonight, Dempster had all his pitches working. A good split-finger, a good slider and good life on his fastball. He went the distance,'' Pineilla said.

Pirates starter Kevin Hart (4-9) made his second start against his former team since being acquired from the Cubs in a five-player deal July 30. The troubles continued from the first inning for Hart, who is 1-8 in 10 starts since being acquired from the Cubs.

The Pirates, who were shutout for the 17th time this season, have dropped 17 of their last 18 road games.

Ryan Theriot led off the first inning with a walk off Hart, then went to third on Kosuke Fukudome 's double. One out later, Micah Hoffpauir hit a bouncer to first baseman Garrett Jones . Jones made a low a flip to Hart, who was running to first to cover the base but Hart dropped the ball and was charged with an error as Theriot scored. Baker followed with a two-run double to give the Cubs an early 3-0 lead.

After Pirates second baseman Delwyn Young committed the Pirates' third error of the game to load the bases in the fourth inning, Lee hit a two-run single and Hoffpauir drove in a run on a fielder's choice.

''We played terrible behind him. He was misfiring, but he battled. We make some plays, it's a lot different line score for him,'' Pirates manager John Russell said. ''He made some adjustments. I thought that after the first inning he settled in and started throwing better. Again, we played so bad behind him it's a tough read.''

Hart allowed six runs, three earned, on six hits in four innings after the Pirates came off a series of winning three of four from the Dodgers.

''It was one of those freak nights. It's tough,'' Hart said. ''We played a really good series against L.A. and we wanted to carry it over and finish this season really strong. It's tough to come in and do what we did tonight.''

NOTES: Before the game, Piniella took exception to a column questioning his passion as a manager. ''We work exceedingly hard here as a staff and if you want to stick around and be here 'til 1 O'clock, 1:30 in the morning, when the parking lot is closed when we're having meetings on how to get our team better you will see that we're very interested and take a lot of pride in what we do,'' he said. ... Cubs reliever Kevin Gregg is out of for the season with cracked rib cartilage. ... Cubs 3B Aramis Ramirez missed the game with a sore shoulder. ... The Pirates claimed right-handed reliever Anthony Claggett off waivers from the New York Yankees . ... The Cubs last had six consecutive winning seasons between 1967-72. ... According to the Pirates Web site, the club will retain pitching coach Joe Kerrigan for the 2010 season and will relieve Rich Donnelly from his duties of baseball operations adviser.