If it wasn't enough to shoulder the likely label of NFL franchise centerpiece, Todd Gurley and Melvin Gordon seem destined to one day assume an even bigger charge: savior to an entire position. Most signs point to the workhorse running back becoming a thing of the past, a quaint vestige to be filed alongside Dan Dierdorf's mustache or anything involving Ryan Leaf.

The proof is in the numbers -- from 1998-2012, the average season featured nearly eight 300-carry running backs, while only two a year have galloped past that hallowed marker since then. The proof is also in the sadness that frosts the fringes of former marquee back Steven Jackson's eyes as he pleads us all to "Save the Running Back" from inevitable extinction.

Thankfully, the meteor hasn't hit quite yet.

In March, NFL owners reversed recent course and opened their coffers for some of today's workhorsiest of running backs. Seattle's Marshawn Lynch snagged a two-year, $24 million extension while DeMarco Murray and LeSean McCoy landed with new teams, in Philadelphia and Buffalo, for deals averaging $8 million a year. That's a significant upgrade for a position which, on the whole, had plummeted to an average salary range commensurate to the kicker. It's also a red herring.

The marquee back is still very much in trouble. Such players' effectiveness nosedives by their late-20s, which is bad news for a Lynch-Murray-McCoy cohort whose average age is 28. Indeed, in terms of on-field production only, it's extremely rare to find a star veteran back of more than six years who can deliver even half the value per carry to his team than his younger version could. That even applies to the ageless Frank Gore, as the chart below shows.

The league's brass know metrics is a cold mistress who hates running backs on the wrong side of 25. This is one reason they have increasingly shifted to a "running back by committee" approach with the potential to wipe out the need for a franchise back altogether. Unless, of course, the strongest NFL draft class of running backs in years comes to the rescue.

So how did this trend begin, anyway?

The league's shift away from the running back is actually as old as Frank Gore's knees. Consider the last time NFL teams called more run plays than pass plays was 1983. Yet so long as Emmitt Smith, Thurman Thomas, Barry Sanders, Marshall Faulk and a young LaDainian Tomlinson were running roughshod on the scene, nobody could imagine the position's precipitous fall.

Sure, passing numbers kept creeping upward, along with the worth of the quarterback and left tackle relative to the rest of the team, but the offensive and financial pies, as a whole, were getting bigger. Few fretted some slices grew faster than others. And even fewer had figured that "so much of what a running back does depends on how well his offensive line plays and how much space is created for him by his quarterback's ability to throw," as Grantland's Bill Barnwell put it.

Then 2004 happened.

That's when the league began more strictly enforcing its no contact after 5 yards rule. This helped more receivers get open more often, which meant teams started passing even more. And all hell started breaking loose.

Every other high school in the nation not already running a variant of the spread offense and playing 7-on-7 soon jumped aboard. Passing to set up the run became way more legit. As the number of short passes going to receivers, tight ends and supplementary backs -- especially on first down -- rose, demand for the workhorse back dropped. Quarterbacks started being able to beat other skill positions in the 40-yard dash. Offensive linemen forgot how to emulate asphalt pavers and in the process might have forgotten how to be real men.

In the last decade, the wreckage has been almost total. The conflagration that was Adrian Peterson's reputation didn't help last fall. And so, a new world order emerges in which all the singular, magnificent glory that used to belong to someone like, say, Terrell Davis, is broken into shards named "Shane Vereen," or "LeGarrette Blount" or "Jacquizz Rodgers."

"Almost everyone has gone to a backfield-by-committee approach," former Browns GM Phil Savage told Newsday. "As offenses have become more specialized, defenses have mirrored that and it has captured the running back spot as well."

Granted, a shardy world is better than a completely tailback-less one. But know this: This be a world bathed in gray. For when a position's mojo is diffracted into so many lesser parts, said position loses its hold on the hearts and minds of America.

Cost per yard

At what ages do running backs produce the best return on a team's investment? And how much does it matter if that back goes in the first round or not? Using this past free-agent class, let's do a little study. For this, I've stirred up my own metric, which is a player's total cash earnings for one season divided by his yards per touch average. That number is then divided by the player's total yards gained that season.

I've slapped the label "Cost Per Yard" on this metric, but note this number doesn't literally translate to how much it cost the team to pay for each of the player's gained yards. Doing that exact calculation would be unfair to extremely productive running backs who simply got injured during the season.

Rather, "CPY" is meant to roughly symbolize how much of an expense the player represents to the team every time he makes a play with the ball. Durability and total season output matters, but it's only half the equation. The higher the number, the worse for the owner's bottom line. The lower, the better.

In the following table, "Yards" means total rushing and receiving yards gained. "YPT" stands for "Yards Per Touch," or the total number of yards divided by running attempts and receptions.

The most expensive running back seasons, by cost per yard (minimum 100 touches):

Running back Season Yards Touches YPT Total cash earnings CPY Darren McFadden 2009 602 125 4.82 $16,684,000 $5,755 DeAngelo Williams 2007 971 171 5.68 $20,500,000 $3,718 Darren McFadden 2013 487 131 3.72 $6,678,584 $3,690 Reggie Bush 2007 998 230 4.34 $13,675,000 $3,158 Darren McFadden 2011 768 132 5.82 $11,200,667 $2,507

Estimated total cash earnings according to data compiled by Spotrac.com and OverTheCap.com.

Zooming out, let's take a look at the complete data for the former first-round picks who have been in the league a minimum of four years.

As you can see, before the most recent collective bargaining agreement in 2011, teams signing first-rounders at some point paid out the nose for it -- often because of hefty signing bonuses and other incentives. As a whole these first-rounders average a CPY of $954. So, as a point of reference for those of you out there thinking like a boss: Three digits = good. Four digits = bad.

Then there's an off-the-charter like Darren McFadden, who notched an obscene $5,755 CPY his second season. Raiders fans can thank a torn meniscus, one of D-Mac's many injuries during his time in Oakland, for that.

Compare the CPY for the first-round picks to the second- and third-rounders, listed here.

Any wonder no running back has gone in the first round since 2012?

On the whole, these guys have cranked out a CPY of $403, less than half of what the first-rounders cost your fave team's Rich Uncle Pennybags. That's a helluva Groupon deal 32 front offices have hacked into.

DeMarco Murray, king of this subset, was an absolute steal during his four years in Dallas before vamoosing to Philly. It's unknown if the Cowboys will take Gordon or Gurley with their No. 27 pick overall as his long-term replacement. What's almost certain is that, if Dallas does take either of them in the first round, neither will match Murray's bargain rate value over the last few years. The irony is that even if the Cowboys are to beat the odds by picking up a first-rounder who produces like a young Chris Johnson or DeAngelo Williams -- who had the best early-career CPY's of our first group -- they may need to risk enraging fans by unloading mid-20s Gurley/Gordon before he starts going down the same high CPY arc late-career Williams and Johnson have.

Let's now look at the five best bargain seasons from our running backs since 2006. To make the cut here, the RB had to have had at 100 touches:

Running back Season Yards Touches YPT Total cash earnings CPY Frank Gore 2006 2,180 373 5.84 $350,000 $27 Ray Rice 2009 2,041 332 6.15 $385,000 $31 Ray Rice 2011 2,068 367 5.63 $600,000 $51 Ben Tate 2011 1,040 188 5.53 $405,000 $70 Justin Forsett 2009 969 171 5.67 $385,000 $70

Speaking of bargain rates, let's now look guys chosen in round four and beyond.

You won't get many sexy names this far down, but team executives have decided over the last few drafts they don't care as much for big names as deep pockets. With an average running back CPY of $386, these are the rounds CFO's dreams are made of.

Sometimes, it's still possible to pick up "stars" in these rounds. Ahmad Bradshaw and Justin Forsett come closest here from the most recent free-agent class. Bradshaw has racked up four campaigns in the 1,000-yard range, but the 29-year-old's 2014 season was cut short by a fractured fibula. Meanwhile, a consistent, dependable running game is one of the main obstacles that keeps Indianapolis from breaking ahead of nemesis New England, its co-favorite for the 2016 AFC championship.

Last season, Raven Justin Forsett became the rare back with a career year at age 29 or older. That's partly due to fortune -- unexpected playing time opened up after Ray Rice things happened and Bernard Pierce was injured -- and almost certainly attributable to the fact Forsett was part of a healthy number of running back committees in his first seven years, racking up only a total of 347 rushing attempts. His body is far less damaged than many other marquee backs in their late-20s. The former seventh-round pick cashed in this offseason with a three-year deal worth about $3 million a year.

Forsett's story could be a how-to manual for the modern young back, who's much more likely to land in a committee situation than a Ki-Jana Carter-y one. Forsett is an inspiration to others toiling in an obscurity they could hardly imagine as superstar backs in high school and college.

Take Ka'Deem Carey, a fourth-round pick in 2014 who finished his rookie campaign in Chicago with a grand total of 36 rushing attempts and five receptions in 14 games. The downgrade likely wasn't a shock to the former University of Arizona All-American. He'd seen the writing on the wall before last year's draft when he joked someone should have told him in high school running backs were being phased out as fast as flip phones, according to azcardinals.com. "Nowadays, they're like you've got to go second, third round. I'm like ‘Why in the hell didn't you tell me this a couple years ago, that running backs are going extinct? I definitely would have went to corner or something."

Ben Tate's currently where Carey would hate to be. The 26-year-old back opened his career with a bang in 2011, but each season afterward has progressively become more expensive in terms of CPY. This isn't a sustainable trend, though, as his overall production has waned since 2011. Last spring, Tate shared Careyesque thoughts about his position with Si.com: "I would've been something else, for sure. I'd have been a safety. I had the opportunity play it in college, but I wanted to be the guy to get the ball. I had no idea the position would be devalued, but hopefully I can break that trend."

Tate did not break said trend last season in Pittsburgh. He is currently unsigned.

To summarize, here are the averages for running backs by round:

Draft round Yards Runs Recs YPT Total cash earnings CPY Round 1 71,446 12,145 2,340 4.93 $336,030,845 $954 Rounds 2-3 38,818 6,740 1,194 5.64 $89,407,750 $403 Rounds 4+ 29,356 4,309 1,344 5.19 $58,829,617 $386

Enter, the Gurley Man

Todd Gurley and Melvin Gordon headline what many believe is the NFL's best running back draft class since 2008. Their college numbers are stunning: Gurley averaged 7.4 yards per game for an SEC team last year before sidelined by an ACL tear. An NFL talent evaluator has tabbed him as the position's most promising prospect since Peterson. Meanwhile, Gordon rushed for 29 touchdowns and nearly 200 yards a game.

Either one of them could be the kind of piece pushing a contender over the top. Add a healthy Gurley, for instance, to a powerful line like the Cowboys' and it's doubtful Dallas misses much of a beat sans Murray.

Still, will Gurley drop as low as No. 27 to Dallas? Could Gordon?

In a previous era, both men are bonafide top-15 picks. Injury concerns with Gurley, as well as the position's overall devaluation, mean there is a chance one slides out of the first round.

A raft of potential draft day steals will follow these two. Watch one of the following second-, third- and lower-rounders make some employer very happy in 2015 by producing the lowest CPY of any running back in the league: Jay Ajayi, Tevin Coleman, Ameer Abdullah, Duke Johnson, T.J. Yeldon or Mike Davis. The irony is that performing at this level, with a high workload, may ultimately hurt them.

The process began long before they ever entered the draft, as Slate's Josh Levin noted: "The quality that gets you the most notice and attention and touted as a potential great player is the same one that hastens your demise. When you see someone like [Leonard] Fournette or Todd Gurley running over dudes in an uncompensated manner, you can just see the cash register running backwards."

In terms of on-field value only, the running back position may be the only one in major pro sports where rookies consistently outproduce veterans. Little on the horizon portends change here. Still, there may be one shred of hope for those hoping for the Return of the Marquee Back, a small, quilted comfort to lay on Steven Jackson's knees as he rocks sagely on the front porch.

As more college teams keep going spread and no-huddle, they increasingly produce smaller, shiftier hybridized linebacker/backs to combat all that speed. But in the process, they sacrifice the kind of mass that used to be vital to slow good run games, as Minnesota Vikings coach Mike Zimmer told ESPN.com's Kevin Seifert. He predicted the running back will cycle back in vogue. "You get a powerful offensive line against smaller defenders, I think you'll have something. Some team will do it, kind of like Alabama [and now, especially, Arkansas] does in college football. ‘Everyone else is smaller, so we're going to go out and get physical guys.'"

Seifert insinuates such a monster may already be brewing in Buffalo, with the signing of McCoy, offensive lineman Richie Incognito and fullback Jerome** Felton.

In the coming years will the clear-cut No. 1 back regain his place atop our nation's sportscape or fade into obsolescence? Todd Gurley, Melvin Gordon and likely a few others in their gifted draft class are poised to grind out an answer.

**Science has shown that "Jerome" is the second-best first name for fullbacks in the sport of American football, trailing only "Bam."