Carter's Classroom: Cowboys' offense best test yet

Many would have thought the Patriots would have been the best barometer to measure the Steelers defense.

But coming off a strong showing last week against the Ravens, it is the Cowboys who are providing the stiffest test.

The Cowboys lead the NFL in rushing yards per game while also having a quarterback in rookie Dak Prescott who has moved the ball efficiently when required.

Let's get right into the film:

COWBOYS' OFFENSIVE LINE

The Cowboys' offensive line does several things very well, but the biggest difference against the Steelers will be whether that group can get past the defensive line and attack the linebackers.

The Steelers' woes in defending the run have mostly occurred when their linebackers were not able to make the correct reads and maintain gap responsibility.

The Cowboys' offensive line has done a very good job chipping from defensive linemen to the linebackers and allowing Ezekiel Elliott to make plays against defensive backs.

Watch the center and guard to the left of the screen as they start with a double team on Domata Peko, and the guard then moves to seal off Rey Maualuga to create the seam in which Elliott needs to accelerate into the secondary.