“X-factor” is a term open to interpretation. An X-factor can be someone who hasn't been a contributor in the past, a player that steps up in the new season. It can also be someone who impacts the game beyond the box score, a locker room leader, or a veteran presence.The Dallas Cowboys' “X-factor” is a player like no other in the NFL. The Cowboys' X-factor is someone capable of impacting a football game in ways no other player in the league can.

Dallas Cowboys' X-factor: Micah Parsons

Parsons' value, and what sets him apart from the other elite defenders in football, is his versatility.

The analytics on Parsons as a pass-rusher are elite. Pro Football Focus' Sam Monson noted in his ranking of the best 50 players in the NFL that Parson's 25.3% pass-rush win percentage was the best in the league last season. That means Parsons, as a rookie, generated quarterback pressure more efficiently than players like T.J. Watt, Myles Garrett and Aaron Donald.

Parsons only moonlights as a pass-rusher. The former Penn State star played 540 snaps lined up in the box as a linebacker during his NFL debut, using his elite sideline-to-sideline speed to become Dallas' second-leading tackler with 84. The quarterback pressures Parsons generates might make more headlines, but he part he plays in the Cowboys' run defense is arguably more valuable.

Parsons has talent to spare. There are very few linebackers in football who get after the quarterback the way he can. Even fewer can switch gears and patrol the middle of the field at a high level as well. What might put Parsons over the top as a player is the defensive coordinator the Cowboys hired to help him develop into a perennial All-Pro and centerpiece of the defense for years to come.

Dan Quinn helped bring some of the best defensive players of yesterday to the forefront during his time with the Seattle Seahawks. Bobby Wagner, Kam Chancellor, Richard Sherman and more all became the best versions of themselves with Quinn pulling the strings defensively.

Parsons has as much raw talent as any of those players, and he's more versatile than all of them. Quinn will be able to dream up all kinds of ways to use his number one weapon in Dallas' defense. If history is any indication, the results should be special.

There are a lot of candidates for the X-factor title on Dallas' roster. Players with a weak track record but high ceilings like Kelvin Joseph can stake a claim. Zack Martin is a veteran leader in charge of a young group of Cowboys linemen, easily fitting that mold as well.

What makes Parsons a true X-factor is the fact there isn't another player in the league who can do what he does. Lots of teams have an elite pass-rusher or a quality field general at linebacker. There isn't a single team in the league that can claim a player who does both, except for the Cowboys.