The Dallas Cowboys haven't had the season they envisioned, and there could be changes in store for their coaching staff. While Mike McCarthy's job is considered safe, NFL Network's Ian Rapoport reports that the defensive staff could be on their way out.

The Cowboys come into Week 14 with a dismal 3-9 record and have looked awful on both sides of the ball. Of course, it should be noted that the offense hasn't looked nearly as explosive since Dak Prescott suffered a season-ending ankle injury in Week 5.

Given that, McCarthy and Kellen Moore — the offensive coordinator of the Cowboys — could get a free pass due to the injuries on offense. However, the same likely can't be said for Mike Nolan, who is in his first season as the defensive coordinator in Dallas.

Before joining the Cowboys, Nolan spent three seasons as the linebackers coach of the New Orleans Saints. He also had 17 years of experience as a defensive coordinator and four years of experience as the head coach of the San Francisco 49ers from 2005-2008.

Through the first 13 weeks of the season, Nolan's defense is the 24th-ranked defense in terms of yards allowed per game (383.6) and have the 32nd-ranked defense in terms of points allowed per game (32.8). In addition, the Cowboys have struggled to create turnovers, recording only five interceptions, which is the third-fewest in the NFL.

It's unlikely that Jerry Jones is going to part ways with McCarthy after one season at the helm. On the other hand, Nolan could be headed to the unemployment line due to the abysmal play of the defense in Dallas.