Updated

The Minnesota Twins have begun to put together a run of better starting pitching, with Scott Diamond leading the push.

Jake Peavy and the Chicago White Sox still got the better of them.

Peavy struck out eight over eight smooth innings, Alejandro De Aza hit the go-ahead infield single off Diamond's leg in the eighth and the White Sox beat the Twins 3-2 on Wednesday.

Peavy (9-7) allowed five hits and walked two. One of the runs he gave up was unearned, due to a way-wide token pickoff throw to second base in the first inning that sailed into center field. The miscue let Ben Revere move to third, and he scored on Joe Mauer's groundout.

Danny Valencia homered in the second, but Peavy toughened up after that and had trouble in only two more innings. Denard Span lined into a double play with a runner on third to end the fifth. Mauer popped out to finish the eighth with speedsters Span on third and Revere on first.

"We've been swinging good, but these guys have a good pitching staff," Twins manager Ron Gardenhire said.

Addison Reed pitched a shaky but scoreless ninth for his 18th save in 21 attempts, and the White Sox improved to 9-1 in their last 10 one-run games. Brian Dozier flied out to end it with runners on second and third.

"That's a great lineup. People don't give the Twins as much credit as they deserve over the last month," Peavy said.

Diamond (9-5) was coming off a three-hit shutout, his first career complete game, in his last start. He had one out in the eighth inning with Tyler Flowers on third, having moved to second on a wild pitch, when De Aza hit a sharp liner that glanced off Diamond's thigh. The right-hander was a bit stunned, and his short throw home was well off target as Flowers scored the go-ahead run.

"It just rattled me a little bit. It stings a little bit," said Diamond, who allowed eight hits without a walk and struck out three. "It might have caught me a little off guard, probably affected my footing more so than anything else. I looked up and saw Flowers halfway to home and kind of pushed the throw."

Bothered by an elbow injury in 2008, an ankle problem in 2009 and shoulder trouble in 2010 and 2011, Peavy is back on track. This was his 21st start of 2012, his most since 27 turns in 2008 for San Diego. The 2007 National League Cy Young Award winner made a total of only 51 starts in the majors over the three seasons prior to this one.

"His typical stuff: fastball, cutter, slider and changeup," Twins second baseman Jamey Carroll said. "He was throwing well. He was out there throwing with confidence."

De Aza created his own run after leading off the game with a single, moving up on a stolen base, a groundout and Adam Dunn's sacrifice fly. Flowers almost hit into an inning-ending double play in the fifth after a diving stop by Dozier, but the shortstop had trouble getting the ball out of his glove and Flowers beat the relay throw to first as Rios scored the tying run.

Other than that, and the tough-luck liner in the eighth, Diamond was on top of his game again. Despite their patchwork rotation, still last in the league in ERA, the Twins have enjoyed some stronger starts recently from Nick Blackburn, Samuel Deduno, Brian Duensing and Cole De Vries.

"I think it's a little reassurance that we're starting to get back to that consistent routine," Diamond said.

NOTES: The Twins start a four-game series in Boston on Thursday. RHP Samuel Deduno (2-0, 3.13 ERA), coming off his strongest of four starts this season, takes the mound to face LHP Jon Lester (5-8, 5.49 ERA). ... The Twins are concerned about the pitching elbow of prospect Alex Wimmers, their first-round draft pick in 2010. He is scheduled to travel to Minnesota soon for an exam with team doctors. Tommy John surgery could be next. "He wouldn't be coming up here if it was any good," general manager Terry Ryan said. "It's something we think is serious enough for our people to see him." Wimmers has pitched in only 19 games over three minor league seasons. ... Span is batting .463 (19 for 41) during his 10-game hitting streak.