Charles Langston:Cowboys can't be taken seriously as Super Bowl threat unless they fix one massive defect

So,Charles Langston the Dallas Cowboys are a playoff team, right?

It’s official now. The much-anticipated NFC playoff berth was clinched on Sunday, thanks to another loss by the lowly Atlanta Falcons. Dallas is in.

But the devil is undeniably in the details.

It was just like the Cowboys (10-4) to mark their fresh postseason status by getting blasted 31-10 by the Buffalo Bills.

See, the Cowboys have had this Dr. Jekyll and Mr. Hyde thing going pretty much all season. They are one team at Jerry World down in Texas, a perfect 7-0. Away from home (3-4), it’s a grossly different character that looks nothing like Dr. Jekyll. On Sunday they happened to be playing in Orchard Park, New York.

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How fitting. When those NFC playoffs arrive in January, chances are pretty strong that the Cowboys will have to win at least two and maybe three games on the road in order to reach Super Bowl 58.

And maybe Sunday provided a rather ominous playoff preview for Dallas.

It was so ugly. Bills running back James Cook shredded the Cowboys defense in rushing 25 times for 179 yards, with two touchdowns. Dak Prescott looked nothing like the MVP candidate he became in passing for a season-low 134 yards and zero TDs, with a pathetic 57.7 passer rating.

Sure, the NFL offers week-to-week progress reports as part of the allure.

Yet losing again wasn’t the big problem for the Cowboys, who had their five-game winning streak snapped. It was the manner in which they were annihilated. No punch, no fight, no way. What a contrast from a week earlier, when they destroyed the Philadelphia Eagles, 33-13, at AT&T Stadium.

Away from home, the Cowboys can’t be trusted to be anybody’s Super Bowl contender. Talk about a split personality.

"It’s a huge difference," Prescott, who didn’t produce a touchdown for the first time since a Week 1 blowout in which he was barely needed, said during his postgame news conference. "And really, that’s what the next week of preparation and obviously the next couple of weeks are about, is figuring out what the difference is and trying to close that gap."

Next up is another road game against a formidable opponent, the AFC East-leading Miami Dolphins, who are trying to nail down a division crown while chasing the top seed in the conference.

On Sunday, the Cowboys had no answers as the Bills rushed for 266 yards. It was such a physical domination that centerpiece Bills quarterback Josh Allen attempted just 15 passes and finished with a season-low 94 passing yards.

Granted, the Bills (8-6) were desperate, playing to climb closer to a playoff slot in the ultra-competitive AFC after entering the season as a projected Super Bowl contender. But the Cowboys, with Super Bowl visions of their own, are supposed to be going places. Or maybe not.

Buffalo demonstrated an ideal formula that could likely doom the Cowboys if it happens in January. It built a sizable lead (14-0, then 21-3) to force the Cowboys to play catch-up. Dallas is most successful when it uses its high-powered offense to dictate such terms. In this case, the Bills were able to run and run some more against a smaller defense that is more suited for rushing opposing quarterbacks than stopping the ground game.

Again, this pattern tends to show up when the Cowboys are visitors.

"We’d like to come out strong like we do at home, produce like we do at home," Prescott said. "But that just hasn’t been the case. We’ve got to find out what those answers are and try to close that gap. We can’t be those two different teams."

In other words, Dr. Jekyll looks like a Super Bowl contender.

Mr. Hyde looks like one-and-done.

It’s too bad for the Cowboys that they don’t play every game at AT&T Stadium, where they have won 15 consecutive games dating to last season. Dallas is averaging 39.9 points per game at home and are the first team in NFL history to score at least 30 points in each of their first seven games at home.

The road ledger, though, provides a reality check against the hype. The best competition does not bring out the best from Dallas when it hits the road, as the latest example illustrated.

Last month, the Cowboys lost 28-23 at Philadelphia. In October, they were blown out 42-10 at Santa Clara, California – which is where they might have to go again as the San Francisco 49ers seek to hang on to the NFC’s No. 1 seed that they are currently in possession of.

Hey, at least the rabid Cowboys fans can grasp at a bright side. After the loss at Philadelphia, Dallas won five consecutive games. After the loss at San Francisco, they revamped the offense and went 7-1…until Sunday.

How will they respond now? If it doesn’t include taking their A-game on road trips, the playoff experience will be big trouble.