CHICAGO -- Ken Williams is perplexed.

Not in a general way, as in why a team that has the talent to be a playoff contender sat 7 1/2 games behind the Tigers in the American League Central as of Wednesday.

The general manager's particular confusion has more to do with the White Sox lack of success against teams that aren't exactly having much success.

"You ask me if I'm perplexed, and I'm sure there's a stronger word," said Williams while sitting in the White Sox dugout prior to Wednesday's game with the A's. "But I can't think of it right now."

Here are the results that frustrate Williams, and the entire organization, for that matter.

In respective four-game home series against the Yankees, Rays and Red Sox, the White Sox won three games each. Yet they have a 1-4 record at home in 2009 against the A's and have dropped recent home series to the Indians and Orioles.

Losing two of three to Baltimore, from Aug. 21-23, started a stretch of 20 games played in 20 days for the White Sox, which basically took them out of contention.

"That's White Sox 2009," said manager Ozzie Guillen of his close-to-.500 team's strange inconsistency. "If you want to compete in any season, you beat the [heck] out of teams with a losing record and you fight against the other ones. We do totally opposite of what we should do."

"For the first person who can explain it to me, I would love to hear it," Williams said. "I'm looking for answers."

All of the games obviously count the same, as catcher A.J. Pierzynski pointed out when asked for an explanation to this specific question. But what might ultimately separate the White Sox from playoff contention is their inability to beat teams out of playoff contention.

"You try to win every game, but it has been an up and down year," Pierzynski said. "Look at our record, and it will tell that we haven't put things together for a long streak. It's frustrating in that account."