Heading into the 2015 NFL draft, the Dallas Cowboys desperately needed a running back. Fresh off setting the team's single-season record for rushing yards with 1,845 in 2014, DeMarco Murray signed with the Philadelphia Eagles in free agency.

The Cowboys had signed Darren McFadden to a two-year contract, but that wasn't supposed to stop them from drafting a running back.

One prospect who was frequently connected to the Cowboys at the time was Miami product Duke Johnson, a 5-foot-9, 207-pound back billed as an effective zone runner with an exciting skill set.

Fast-forward to the draft, and the only thing that may have prevented Johnson from dawning the star was Randy Gregory's precipitous fall from top-10 pick to the late second round. Dallas couldn't pass up the chance to select the most talented pass rusher in the class with pick No. 60.

Johnson was selected 17 picks later by the Cleveland Browns, and by the time the Cowboys went on the clock with their third-round pick (No. 91), all of the starting-caliber running backs were gone, forcing them to go in another direction.

Four years later, the Cowboys may again be capable of acquiring Johnson, as the team was rumored to be one of the parties interested in trading for the Browns' backup running back. Because Cleveland signed Kareem Hunt last month, Johnson's role should be severely diminished in 2019, which is why teams are inquiring about trading for him.

In regard to NFL trades, compensation is always king, so the Cowboys would need to be wise with any potential compensation given in return for Johnson's services. But if the price isn't too steep (say, a fifth-round pick) and the rumors are true, trading for Johnson should be a no-brainer.

Why? Glad you asked:

Effective zone runner

In the NFL, there are typically two types of blocking schemes on run plays: gap and zone.

Gap runs (such as "Duo") require the offensive line to displace specific defenders in a particular fashion to create the desired running lane.

Zone runs (such as outside zone), on the other hand, have linemen move on the same track initially before blocking the defender in their zone. In this scheme, running backs don't have a particular gap to run through. Instead, they must follow a designed path before making a bend, bang or bounce read based on certain defenders' leverage (his location relative to the blocker).

While the Cowboys use a wide variety of run concepts, they would still be categorized as primarily a zone-blocking team because two of their top three concepts by usage were inside zone and outside zone, according to Pro Football Focus. That matches Johnson's skill set.

Since his Miami days, Johnson has been the most comfortable on zone concepts, displaying the appropriate pacing, vision and burst to consistently find success. Here's a great example:

On the play above, the Browns are running a strong-side (strength of the formation is play-side) outside zone against the Houston Texans' talented defense.

Once he receives the ball, Johnson immediately reads the leverage of the end man on the line of scrimmage, who happens to be Pro Bowl edge defender Jadeveon Clowney (No. 90). With Clowney pinned inside, Johnson has a clear bounce read to run the ball outside, but note the position of the "MIKE" linebacker (No. 55):

Houston's MIKE linebacker read the play well from the jump, and his initial steps put him in position to outpace the right guard's block and meet Johnson as he crosses the line of scrimmage after bouncing the ball outside.

Johnson's excellent vision enables him to identify the linebacker's path and react in a way that forces him to alter his path, allowing Johnson to break the line of scrimmage unencumbered.

Notice how Johnson presses inside, selling a potential bang read with a slight head nod toward the backside A-gap. This gets the MIKE linebacker to hesitate just long enough for the right guard to make contact and latch onto his frame, preventing him from effectively pursuing Johnson.

This allows Johnson to get to the edge before cutting upfield for a sizable gain.

This is exactly the kind of vision, pacing and burst teams look for in zone running backs. Johnson routinely makes the correct reads on zone concepts while showing an advanced understanding of how to manipulate defenders at the second level.

Elusive ball carrier

In accordance with his zone-running ability, Johnson also is one of the more elusive backs in football.

Despite just 40 carries for 201 rushing yards (5.0 yards per carry) last season, Johnson still showed off his elusiveness as a ball carrier. He forced 12 missed tackles and averaged 4.13 yards after contact per rush attempt, according to PFF, while running behind a mediocre, Joe Thomas-less offensive line.

That 4.13 yards-after-contact-per-attempt average means that just 0.87 of his average yards per carry came before contact, which paints an accurate picture of the blocking (or lack thereof) he saw as a ball carrier.

Johnson's elusiveness came in handy as he routinely had to deal with penetration by opposing defenses. Here's a great example:

On the play above, the Browns are running a gap concept that is commonly referred to as one-back power, where there is a double-team at the point of attack (left guard and left tackle doubling the 3-technique), the tight end kicks out the play-side edge defender and the backside guard pulls around to lead the running back through the hole (play-side C-gap).

After receiving the ball at the mesh point, Johnson demonstrates effective pacing (short strides) to give the right guard time to pull and lead him through the hole. The Baltimore defense was wise to this concept, as two Ravens defenders (strong safety, No. 23; MIKE linebacker, No. 57) effectively fill the C-gap, meaning one can take on the guard's block while the other one makes the tackle.

Nonetheless, Johnson's effective pacing enabled him to stay balanced and capable of accelerating in any direction. So once the two defenders fill the gap, Johnson is able to swiftly bounce outside beyond the edge defender into open space, giving him an easy path to the end zone.

Johnson's elusiveness enables him to maximize the yards available on a given play and is exactly the kind of trait that is extremely valuable in a complementary running back.

Excellent receiver out of the backfield

Johnson's ability as a traditional running back is valuable, but everyone understands that Ezekiel Elliott is the Cowboys' primary ball carrier. For as talented a player as Johnson is, he doesn't hold a candle to Elliott as a runner.

Still, Johnson has the capability to produce in a myriad of ways, one of which is as a receiver out of the backfield.

Browns have finally fed Duke Johnson and he's been great pic.twitter.com/PWdL3qevRF — Ian Wharton (@NFLFilmStudy) November 4, 2018

Despite his talent as a runner, there's an argument to be made that Johnson is even more effective as a receiver, which makes sense given his career production so far. In each of his four pro seasons, Johnson has accumulated more receiving yards than rushing while seeing more targets than carries in every season except his rookie year.

He has proven to be one of the more talented receivers out of the backfield, finishing 10th in yards per reception (9.1) among the 53 running backs with at least 24 targets. Of Johnson's 47 receptions, 24 went for first downs (51 percent). That, compared to Elliott's 23 first downs on 77 catches (29.8 percent), is impressive.

Johnson possesses soft hands that are capable of making grabs inside and outside of his frame while stationary or in movement. His quickness and change-of-direction ability make him a matchup nightmare for linebackers in the passing game. Here's a good example:

On the play above, the Browns are in a shotgun formation with Johnson aligned to Baker Mayfield's right. Note how the weak-side linebacker is stacked over Johnson's alignment with a slight outside shade. This is an indication that the weak-side linebacker is in man coverage against Johnson with the outside shade aiding the linebacker in covering Johnson to the flats.

Unfortunately for the linebacker, Johnson isn't running a flat route. Instead, Johnson runs a "Texas" route, where the running back sells a flat route before cutting diagonally toward the middle of the field.

Not only does Johnson leave the weak-side linebacker stumbling and unable to provide coverage with the route, he also accelerates past the MIKE linebacker, turning a 5-yard gain into 20-plus yards.

An unnecessary holding penalty by a receiver brought this play back, but it gives a great glimpse into Johnson's ability as a receiver out of the backfield.

Capable of lining up out wide

On top of his ability as a receiver out of the backfield, Johnson also shows the capability to align in the slot or outside, where can provide a huge mismatch against linebackers in space. This play is a great example:

On the play above, Johnson starts in the backfield before being motioned to the slot. Once the ball is snapped, he bursts forward, angling slightly toward the sideline to sell an outside breaking route. As the linebacker bursts outside to defend the out route, Johnson quickly veers inside to cross the linebacker's face and burst downfield, providing the quarterback with an easy throwing window for the touchdown.

With the ability to line him up anywhere, Johnson could be a potent weapon for the Cowboys in a similar ilk to how they once used Lance Dunbar.

The Cowboys could use Johnson in the same vein that the New England Patriots use James White. He can be a dangerously effective option to isolate and take advantage of teams with subpar coverage linebackers.

Final thoughts

Based on skill set and talent level, Johnson would be a fantastic fit in the Cowboys' offense.

He would be the most talented backup Elliott has had in the NFL and capable of taking some of the load off Elliott's plate, which is important -- if the Cowboys give Elliott a lengthy contract extension -- to limit the wear and tear on Elliott's body. And with Kellen Moore as offensive coordinator, the Cowboys can get creative with Johnson's ability to line up and be effective in traditional receiver alignments.

The Cowboys need to get more explosive and creative on offense, and the addition of Johnson would go a long way toward improving both aspects.

For those who scoff at the idea of shipping a draft pick for a backup running back, consider this: Only 8.9 percent of draft selections between the fourth and mid-sixth rounds make long-term impacts on their teams, according to Optimum Scouting's Justis Mosqueda. That percentage falls to 1.5 when discussing players selected from the mid-sixth round and later.

So would you rather have a proven complementary running back with the versatility to affect the offense in a myriad of ways or, at best, a 1-in-10 shot at securing a player with some semblance of long-term viability?

Given their needs ahead of the 2019 draft, the Cowboys will likely look to pick a running back who can contribute in similar ways to Johnson. Therefore, they would be wise to simply acquire the real deal.

The answer is simple: As long as it costs a Day 3 pick, the Cowboys would be wise to trade for Johnson.

Enjoy this post?

See more film room breakdowns from Owning here!

Twitter: @JohnOwning