PHILADELPHIA (CBS) — The Dallas Cowboys are the best team in the NFC East, possibly the NFC. The Cowboys feature a dynamic running game led by Ezekiel Elliott, who's on pace to eclipse Eric Dickerson's 1983 rookie rushing record, the NFL's best offensive line and deep threat in Dez Bryant, when healthy, and a good enough defense to be 5-1 and sit atop the division.

These are things that we know about Dallas.

What do we really know about the 4-2 Eagles?

Not much.

We know that they're incapable of coming back late when down. We know they have a difficult time against quality offensive lines (see the 230 rushing yards the Eagles gave up against Washington) and we know they have wide receivers unable to separate from defensive backs.

It's a team that began the season 3-0 and the surprise of the NFL. Then the Eagles came back to earth in loses to Detroit and Washington, bludgeoned for 737 yards combined in total offense, the bulk of which came against Washington.

But we truly don't know anything yet about Carson Wentz and this team.

Wentz looked good the opening three games and had his issues these last three games, including the Minnesota victory, which was made possible by four caused turnovers against the worst offense in the NFL.

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The Eagles turned the ball over three times against the Vikings, two on Wentz interceptions. Statistically, he's trending downward. He's 52-for-83, for 555 yards, three touchdowns and three interceptions in his last three games. In his first three games, he was 66 of 102, with five touchdowns and no interceptions. The gunslinger in him is beginning to surface. He's not getting away with the chances he took the first month of the season.

Bennie Logan being out creates a huge void in a defensive line that was counted on to do much of the heavy lifting this season. Without Logan to stir chaos, it's left Fletcher Cox to get overwhelmed in the center of the Eagles front and force him into playing beyond his strengths. With the exception of Brandon Graham, the Eagles' defensive line hasn't been much of a factor. In fact, it contributed to the Eagles losses on two costly Cox penalties.

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How the Eagles look against the Cowboys will define them, because right now, they're meh. They're a mediocre team that sprung on the NFL in September to the surprise of many, possibly even themselves.

If they piece together the small broken things, like penalties and turnovers, and Wentz can restrain himself from trying to fit passes into small windows, borrowing a phrase from Eagles' safety Malcolm Jenkins, "and just go back to playing boring, fundamental football," maybe a playoff-caliber team could emerge Sunday night in Arlington, Texas.