So much for a White Sox cruise back into the playoffs.

You know all that talk about how the Detroit Tigers won’t have staying power in the American League Central? About how the season’s too long and their level of experience too short?

Well, maybe that still will prove correct. But as the White Sox approach a series at Detroit’s Comerica Park, one of four they have remaining against the Tigers, it’s the defending World Series champs who have placed themselves in a precarious position.

With a 5.24 staff earned-run average since the end of May, the White Sox can no longer take anything for granted. They’ve been able to avoid a slide because of their deep lineup, but you wonder how much longer that will be true if pitching coach Don Cooper doesn’t get his guys turned around – and that’s not going to be easy to do if the staff-wide decline is the result of the heavy workload in 2005.

That’s what the esteemed John Kuenster believes, and he should know.

Kuenster, editor of the Chicago-based Baseball Digest, covered the White Sox when they won a pennant in 1959 and then slid to third place the next season.

“This year’s team reminds me of the ’60 team,” Kuenster said. “The pitchers who did great in ’59 – Early Wynn, Bob Shaw – were expected to do the same thing the next year, but they couldn’t. They were worn down from the innings, the complete games, it took to win the pennant. It takes a toll the next year.”

Here’s one reality for the Sox: The staff that had a 3.61 ERA a year ago heads to Detroit with a 4.61 ERA. And here’s another one: As a result, the Sox are in a six-for-three playoff battle with the Tigers, Boston Red Sox, New York Yankees, Toronto Blue Jays and Minnesota Twins.

There’s an 11-game gap between Detroit, at the top of this group, and the Twins, at the bottom, with the Sox still ahead of four others. But the seven-game lead they had over the Yankees in the wild-card race on July 9 is down to three. That’s largely because the Red Sox and Yankees outscored the White Sox 47-26 in taking five of six on either end of the All-Star break.

As much fun as it has been to watch Jim Thome, Paul Konerko and Jermaine Dye hit, these aren’t good trends.

It’s also worth noting that the Sox have been healthier than most of the other contenders, who will start getting parts back, and that the general managers of the other American League contenders – most notably Tigers GM Dave Dombrowski – are committed to making some big moves before the July 31 deadline for waiver-free trades.

While the Sox pound their chests about the Thome-Konerko-Dye nucleus, the Tigers have been a better team with guys like Omar Infante and Marcus Thames joining Ivan Rodriguez and Magglio Ordonez in the middle of the order. On Sunday, with Jim Leyland sitting Rodriguez and Ordonez so they will be fresh to face the Sox, they had Infante, Thames and Carlos Guillen in the 3-4-5 spots.

Imagine how much better they might be if they pay the ransom required to obtain Alfonso Soriano, who hit his 29th home run Sunday, or even Bobby Abreu of the Philadelphia Phillies.