The Chicago White Sox were swept in New York by the Yankees last weekend. Manager Ozzie Guillen said this made it a requirement for the Mighty Whiteys to win the upcoming series in Minnesota or they would be finished in the American League Central.

Chicago lost the first two games, putting them at 1-11 for their four visits to the Metrodome dating to September 2008.

The White Sox took the field for Wednesday's matinee as if they believed fully in Ozzie's pre-series opinion: Two losses here meant they were dead, and they already had those.

Twins rookie Brian Duensing pitched seven innings and Chicago did everything in its power to make those scoreless.

Scott Podsednik ran the Whiteys out of the first inning. Jermaine Dye jogged a potential double into a single leading off the fifth. Two innings later, Paul Konerko opened with a single, then Dye bounced to the mound and jogged again to make sure the Twins had time to turn their third of four double plays.

Carlos Quentin followed with a hit to left and was thrown out easily at second base to end the inning.

It was at this point the suggestion was made, "The White Sox might not care, but at least they're stupid."

Mark Buehrle, a professional even when surrounded by indifference, held the Twins to a pair of runs over six innings. It came on Jason Kubel's soft single -- after Guillen ordered a walk to Justin Morneau to load the bases in the sixth.

Apparently, Ozzie wasn't much sharper on this afternoon than his players, since he had not noticed that Morneau was fully engaged in a familiar late-summer swoon.

Familiar? Morneau has one home run in the past month. That puts his August/September home run ratio since 2006 at one per 48.3 at-bats. Over the same four seasons, he has one home run per 15.6 at-bats from April through July.

Morneau's latest 0-for-3 didn't seem to matter as the Twins carried the 2-0 lead into the ninth. The White Sox -- eager to get on the charter flight back to Chicago -- made two quick outs.

Joe Nathan was 0-2 on rookie Gordon Beckham, then reverted to what has become his late-summer approach: trying to get the hitters to chase bad pitches rather than making good ones.

Nathan had a disastrous August/September stretch last season, and now -- in the crucial days of another division race -- he has again turned as frightening as a ride-along with the vampire sheriff in "True Blood."

He has been shaky since blowing a save in Kansas City on Aug. 21. The Twins came back to win that game. He needed help from umpires and fielders to avoid blowing two or three more.

Then came Wednesday.

Nathan messed around until he was 3-2 on Beckham, and then the Sox's future star homered to left. Nathan messed around until he was 3-2 on Konerko, and then threw a slider that moved three inches, right into the veteran slugger's happy zone, and the Sox had gone back-to-back.

Late in 1984, third baseman Gary Gaetti lamented his error as the Twins blew a 10-run lead by saying, "It's hard to throw when your hands are around your neck."

Nathan responded to the homers with the same approach, walking the next two Sox and getting hooked. Matt Guerrier permitted both to score and Chicago -- willing to accept a shutout loss a few minutes earlier -- had a winning four-run rally.

Back in July, these Twins also achieved defeat after holding a 10-run lead in Oakland, but that will not be the loss to remember when the schedule runs out on Oct. 4 and the mediocre Central has escaped their grasp.

That loss will be Wednesday's, with the Nathan meltdown, because it came when the Twins were playing their best ball of the season: winning 11 of 14 and feeling optimistic that they could reel in Detroit.

The change in outlook was pervasive in the home clubhouse. The Twins were such a rattled bunch that even Rick Anderson, the usually affable pitching coach, fired some profanities when asked, "What's wrong with Nathan?"

Profanities are common in a clubhouse, but the question still stands: What's wrong with Nathan? And you could add Morneau.

Patrick Reusse can be heard 5:30-9 a.m. weekdays on AM-1500 KSTP. • preusse@startribune.com