In Week 15 of the NFL season, the Dallas Cowboys faced off against the Buffalo Bills.

The Cowboys got some good news going into the matchup, as they officially made the playoffs before even taking a snap in today's game. That would be the end of the good news on the day.

The Cowboys ended up getting walloped by the Bills and it revealed a troubling trend. 

In the Cowboys' four losses on the season, three of them have been by multiple scores. And in all have them nothing seemed to be going right, but there was a common trend: The run defense getting exposed.

In the Cowboys' Week 3 loss to the Arizona Cardinals, the Cardinals ran for 222 yards. Back in Week 5, during their loss to the San Francisco 49ers, the 49ers ran for 170 yards.

Fast forward to today versus the Bills: One player alone had nearly 200 yards rushing. In total, they ran for 266 yards. 

The one Cowboys' loss that was less than one score was their loss to the Eagles in Week 9. In that game, the Eagles ran for 109 yards. That is a trend.

So now the question is what is the primary issue? And how can they fix it? Dan Quinn has gotten his fair share of praise in his time as Cowboys defensive coordinator, and rightfully so.

However, there is a flaw in his defense. It is in the personnel he deploys.

Quinn has an affinity for athletes, and finding homes for them in his defense. We have seen it with Jayron Kearse and Markquese Bell. Both of these players were once safety but have moved to linebacker in the Cowboys' defense. 

While they have had their fair share of highs, they are getting picked on this year when it comes to the run.

Being former safeties, they are obviously going to weigh less than a traditional linebacker. This allows for teams to go into a heavy formation when they are in and potentially get an offensive lineman on them when they run toward them. 

In Week 3 and Week 5, Jayron Kearse's average depth of tackle was 8.0 yards. Against the Bills, Kearse's average depth of tackle was 11.67 yards (!!!).

In every other week, it has been 6.86. While that might not seem like a drastic difference, it has had an impact on the defense. 

It is not all doom and gloom for the Cowboys, as we mentioned they are guaranteed a spot in the playoffs. Now it's a matter of fixing what has been exposed in hopes for a deep playoff run. 

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