CHICAGO -- Carlos Guillen got it started with a drive into the right-field seats in the first inning. Magglio Ordonez and Placido Polanco did their part, too.
Justin Verlander (8-4) supplied the pitching to go along with the Detroit offense. He allowed nine hits but just one run in 5 2/3 innings for his first victory since May 27.
"I think they're feeding off each other a little bit," manager Jim Leyland said. "I think the big thing is our position players have a lot of confidence in our pitchers now and they've earned it."
Guillen had three RBIs with a two-run homer in the first and a run-scoring double in the ninth. Polanco scored three runs and drove in one, and Ordonez had a double, two RBIs and scored twice.
Verlander struck out four and walked three. He was 0-1 with two no-decisions in June after going 4-1 and earning AL rookie of the month honors in May.
"I felt they had been good starts; that's going to happen," he said.
Verlander left after walking pinch-hitter Tony Womack to load the bases in the sixth. Wilfredo Ledezma relieved and Juan Pierre, who had singled twice, fouled out to third to end the inning.
Jacque Jones and Aramis Ramirez had three hits each for the Cubs, who stranded 11 runners and lost their fifth straight.
A day after knocking out Glendon Rusch in the second inning, the Tigers struck early against rookie Carlos Marmol (1-1).
Suburban Chicago native Curtis Granderson led off the game with a triple to the right-field corner, drawing a boisterous "Let's go Tigers!" chant from the visiting fans. He scored on Polanco's single to center.
With two out, Guillen drilled a 1-0 pitch out to right for his eighth homer and a 3-0 lead.
Marmol allowed four runs and seven hits in six innings in his second major league start and fourth appearance -- after holding Cincinnati to a run in six innings in a victory Sunday.
Verlander got in and out of several tough situations.
"It was almost like he wanted to get this thing over before he got 27 outs," Leyland said.
But the Cubs couldn't get the clutch hit.
They had runners on second and third with none out in the second but settled for one run - Ronny Cedeno's RBI single to short center. Henry Blanco, who had three hits Friday, then sent a drive down the left-field line that was ruled foul. Manager Dusty Baker argued to no avail, Blanco lined softly to shortstop and Marmol grounded into a double play.
The Tigers scored three runs in the eighth to stretch the lead to 7-1, with two coming on a triple by pinch-hitter Omar Infante that bounced out of the net above the center-field wall. Leyland came out of the dugout and argued, but had little to say about it afterward.
Pierre, who had the best view, sighed and said, "I don't want to touch that one. They called it a triple, so I played it like that. I couldn't tell."
The Cubs haven't won since taking the final three of a four-game set from Cincinnati and fell 15 games below .500 (26-41) with the loss to the Tigers.
"It's embarrassing," Todd Walker said. "It's not fun to go out there and lose every game, especially when you're giving your heart to it and falling short every time."
There was some good news for Chicago. Mark Prior will make his first start of the season Sunday after missing the first 2 1/2 months with a strained shoulder.
"It's been a long, hard road, but I'm glad that Mark's getting back on the mound," Baker said. "Hopefully, we can keep him on the mound all year long."
Tigers C Ivan Rodriguez was lifted late in the game for the second straight day with cramps. Leyland said he won't start on Sunday, when Kenny Rogers goes for his 200th win. ... Cubs RHP Kerry Wood (shoulder) might pitch a simulated game in Cleveland and could be ready to return from the disabled list as soon as next weekend. "It's certainly a possibility," pitching coach Larry Rothschild said. "I don't want to give a date, but I would think it wouldn't be a long time after he's eligible." ... Blanco started his second straight game at catcher, with Michael Barrett nursing a sore back. Barrett sat out Friday because of his back and a lengthy pregame hearing for his appeal of a 10-game suspension for punching the White Sox's A.J. Pierzynski. ... With a runner on third and the Tigers up 4-1 in the fourth, Cubs shortstop Ronny Cedeno saved a run when he dove to his left to stop Polanco's grounder and threw to first for the third out. ... Detroit's Marcus Thames extended his hitting streak to 10 with a single in the sixth.