MINNEAPOLIS -- Craig Monroe is growing into his new role as a reserve.
Mike Redmond had two RBI for Minnesota, which has won eight of 10 and 12 of its last 14. The Twins remain 2½ games behind Chicago in the AL Central; Detroit is six back.
Marcus Thames hit his second homer in as many games for the Tigers, who lost for the first time in seven games.
It has been a frustrating year for Monroe, who was acquired in November as a potential primary left fielder. Instead he has had to adjust to being a bench player and occasional designated hitter against left-handed pitchers.
The lack of consistent at-bats has led to a number of issues for Monroe who played in 682 games the last five years -- all but 23 with Detroit. He hit 100 home runs for the Tigers in that time.
He says those have been corrected, including a shortened swing with a smaller leg kick, not pulling off the ball and being more situationally focused during batting practice.
"All these things you talk about trying to be a good bench player, I wasn't allowing myself to do it because I had so much success playing every day and having the high leg kick. Now it's a new chapter in my career where I've got to find a way to be a better bench player. I think now I'm starting to take all the strides in the right direction."
Monroe's shot over the centerfield wall in the fourth gave the Twins a 3-0 lead. It was Minnesota's first three-run home run since Monroe did so as a pinch-hitter May 28 at Kansas City.
"It just changed the game. The momentum was instantly shifted," Minnesota starter Scott Baker said. "I'm thankful to see him in the lineup every time we face these guys because you know he's going to do the best he can and probably put some good swings on the ball."
Detroit manager Jim Leyland isn't surprised what his former player did. "Everybody knows he's got power, and I'm pretty sure he's pumped up for us. He's a threat at all times."
Monroe just missed hitting another in the fifth, but it hooked just foul.
"I knew Zach Miner throws a hard sinker. I went into that at-bat knowing he was going to come in," Monroe said. "That's one of the adjustment things where I'm learning how to sit on different pitches. When I know whatever his strength is I'm trying to have an approach to where I give myself a chance. Today I was looking in and got a good pitch to hit, but it just went foul. I wish I could of blew it back fair."
Baker (5-2) wasn't sharp, but won his third straight game for the first time in his 60-start career. He retired 10 of the first 11 Detroit batters before getting roughed up a bit in the middle innings. For the second straight start, he allowed three earned runs in six innings.
One night after the Twins' bullpen gave up the lead in a 5-4 defeat, Brian Bass and Dennys Reyes limited Detroit to one run in two innings before Joe Nathan earned his 23rd save in 25 chances with a perfect ninth.
Five hits to open the fifth chased Nate Robertson (6-7), who was hit hard for the second straight game. Robertson, who allowed a season-high 11 hits in 6 1/3 innings last Thursday, allowed the same amount in four innings Tuesday.
It was his shortest outing since June 5, 2007, when he gave up six earned runs without recording an out. He went on the disabled list the next day with a tired arm. Eleven of 20 Minnesota batters reached base against Robertson, who was aided by grounding the Twins into two of their franchise-record tying five double plays.
"We left a ton of runs out there," said manager Ron Gardenhire.
With runners on second and third with nobody out in the first, Redmond grounded out to first, and Carlos Gomez, who hesitated on the play, was thrown out at the plate.
The Twins got their first two batters on base in the second, but a strikeout and double play kept them off the scoreboard.
Redmond hit into a bases-loaded double play to end the sixth.
"I just made pitches, that's what it comes down to. They had guys on base, but you make pitches and get outs," Robertson said.
Carlos Guillen scored on a wild pitch in the fourth for Detroit, before Baker struck out Matt Joyce and Gary Sheffield with Thames at second base.
Thames two-run homer in the sixth was his 14th in 30 games. Sheffield had an RBI single in the eighth.
Minnesota last grounded into five double plays Aug. 12, 2006, against Toronto. ... 1B Miguel Cabrera pinch-hit for the Tigers. He left Monday's game with a tight left hip flexor. Leyland said he won't be ready to play Wednesday. ... Gomez walked twice for the first time in his career. Minnesota's leadoff hitter now has 14 walks and 83 strikeouts. ... Miner walked a career-high four batters in two-plus innings.