DETROIT - Twins manager Ron Gardenhire had reasons for every move he made in Thursday's 7-3 loss to the Tigers, but it was one of those days when some big ones didn't work.

Afterward, Gardenhire was clearly disappointed. His team had a chance to go 3-1 at Comerica Park this week and had to settle for 2-2.

Lefthander Scott Diamond pitched seven strong innings, but with his pitch count at 91 on a muggy afternoon, Gardenhire turned to his bullpen to protect a 3-2 lead in the eighth.

"I was definitely a little gassed," Diamond said.

Diamond tossed eight innings his previous two starts, but before this game, Gardenhire said the plan is to use the All-Star break to give the lefty extra rest before his next start.

Diamond, who is 7-3 with a 2.62 ERA, has pitched 1132/3 innings between Class AAA and the majors. He also took a line drive off his right shin in the fourth inning, leaving a gash that still was bleeding after the game.

"That really worried us," Gardenhire said. "But -- tough kid -- he went right back out there, and kept battling. He gave us a great start, seven solid innings in that heat."

The Twins have grown confident in their relievers, but heavy use has left the bullpen shorthanded, and it finally caught up to them. Glen Perkins still was unavailable after pitching four consecutive days between Saturday and Tuesday.

Earlier in the week, the Twins gave a similar break to righthander Jared Burton, but he was ready to pitch Thursday.

"He was our closer today," Gardenhire said, noting that Burton was warming up in the ninth.

But the Twins couldn't keep the lead long enough to use Burton like a standard closer. Gardenhire started the eighth with righthander Alex Burnett, who had a 1.77 ERA and hadn't allowed a run in 16 consecutive innings.

The Tigers caught a break when Austin Jackson flared a one-out triple down the right-field line.

"Few inches to the right, it's a foul ball," Burnett said.

Burnett then walked pinch hitter Quintin Berry, putting runners at the corners for Miguel Cabrera.

"I think the walk to Berry was huge," Gardenhire said. "You give up a triple, and you've gotta go after him."

Cabrera, who went 8-for-14 with eight RBI for the series, grounded a hard single up the middle, tying the score. Gardenhire then summoned rookie lefthander Tyler Robertson to face Prince Fielder.

Lefthanders had been 2-for-11 against Robertson, who retired Fielder two nights earlier in a scoreless eighth inning with a one-run lead. This time, with a 1-0 count, Fielder smashed a slider into the right-field seats for a three-run homer to make it 6-3.

"I hung that one a little bit out of the hand," Robertson said. "I think he saw it pretty good, and he hit it out of the ballpark. That happens when you don't make pitches."

Delmon Young followed with a home run off right- hander Anthony Swarzak, and the Tigers celebrated their revival.

The Twins were left to lament the extra damage they couldn't do against Tigers starter Rick Porcello, who allowed 12 hits -- but only three runs -- in 32/3 innings. The Twins also had three runners thrown out at home plate, including Darin Mastroianni on a botched squeeze attempt by Jamey Carroll in the eighth.

"We had chances," Gardenhire said. "The game could have been a different story."