The NFL’s decline in running back value has been gradual, slowly fading over the past decade as football has evolved. But last weekend the crash for feature backs was sudden: Five clear-cut starters (Adrian Peterson, Jonathan Stewart, Doug Martin, Arian Foster, and Ameer Abdullah) went down with injuries, and invaluable Chargers cog Danny Woodhead was lost to a torn ACL.

The ailments run the gamut in terms of severity, from the Buccaneers’ Martin saying that his hamstring issue was only a “slight tweak” to the Vikings breaking the news on Wednesday morning that Peterson would have surgery to repair his torn meniscus and is expected to be out until at least December. No matter how much time these backs miss, though, Week 2 offered a potent reminder of why using high picks and doling out huge contracts to running backs can be a dangerous practice.

Offenses continue to run the ball with less frequency than in the past — in the first two weeks of the 2016 season, the leaguewide rushing percentage was 39.6, down from 40.8 the year before — but the NFL’s shift toward becoming a passing league isn’t the only thing to blame for the tailback position’s drop in value. There’s a host of reasons why high-priced backs simply aren’t staying on the field.

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The image of Peterson being carted away after tearing his ACL 12 games into the 2011 season is indelible, but overall he’s been among the healthiest backs in football in recent years. His 2014 suspension stemming from a child abuse charge pushes him down the list of games started among running backs over the past five seasons, yet he missed just six games to injury during that stretch. Few of his peers have been more durable.

Only six backs started at least 75 percent of their team’s 80 games from 2011 through 2015: Frank Gore (who started 79 and is made of Adamantium), Matt Forte (72), LeSean McCoy (71), Marshawn Lynch (66), Alfred Morris (64) — who wasn’t even in the league until 2012 — and Chris Johnson (62). The landscape is so rough that even players who’ve developed a reputation for being injury prone, such as Jamaal Charles and Foster, are close to cracking the top 10.

In Week 17 of the 2015 season, 14 teams gave a majority of their running back snaps to players who weren’t primary options in Week 1. The list of names features luminaries such as Cameron Artis-Payne, David Cobb, Mike Gillislee, DuJuan Harris, and Jonas Gray. Some of those 14 teams were contenders that rested their best players while the league’s basement dwellers mailed it in, but this phenomenon was also prevalent in the playoffs. In both the wild card and divisional rounds last season, six of the eight participating teams gave a majority of their snaps to former backups.

With their Super Bowl aspirations on the line, offenses were forced to rely on guys like Spencer Ware, Alfred Blue, and Fitzgerald Toussaint (who coughed up a costly fumble in the fourth quarter of the Steelers’ divisional loss to the Broncos). At the most crucial juncture of their seasons, most teams in contention for the championship were relying on their second (or in the case of Pittsburgh and Seattle, third) option at running back. With so many big-name, high-priced options unavailable when it mattered most, the question becomes how important it is for franchises to have one of them.

For a while, the NFL draft seemed to indicate that having a high-profile feature back wasn’t all that essential. The absence of first-round picks at the position in 2013 and 2014 was a constant topic of conversation, but then Todd Gurley (no. 10) and Melvin Gordon (no. 15) ended the drought in 2015, and Dallas took Ezekiel Elliott (no. 4) this spring. Already, though, the prudence of those picks is worth exploring.

After having a nightmarish rookie year, Gordon has been excellent in San Diego’s first two 2016 games, averaging 4.2 yards per carry and showing off power and vision that just weren’t there in 2015. But even as he breathes life into the Chargers’ running game, the makeup of San Diego’s offense inherently limits his value. Woodhead got 68 percent of the team’s offensive snaps in Week 1, even as the Chargers nursed (and then blew) a massive lead against the Chiefs. With their pass-catching back now gone for the season, San Diego brought in former Titans running back and Ken Whisenhunt favorite Dexter McCluster to assume that role.

In that regard, the Chargers aren’t alone. Pass-catching specialists across the league have stolen time from early-down workhorses, no matter how effective those bruisers might be. Martin played only 56.8 percent of the Bucs’ snaps last season in part because Charles Sims is so valuable as a receiver, and the inverse was true for Woodhead (50.9 percent) and Gordon in San Diego. Three-down backs have become an endangered species: Just six backs (Devonta Freeman, Peterson, DeAngelo Williams, Latavius Murray, Lamar Miller, and Gore) played more than 60 percent of their team’s snaps in the 2015 campaign, and only nine others cracked 50 percent.

The Chargers lead the league in rushing percentage (52.3) after finishing 28th (37.1) in the category last year. Racing out to big leads in consecutive games contributed to that, but the team is also clearly trying to preserve Philip Rivers’s skeletal structure, and that means giving about half of the offensive snaps to a pass-catching back like McCluster. In Dallas, Elliott will cede some looks to Lance Dunbar in the passing game, but if last week is any indication, he’ll still get the majority of the work; he took 63 percent of the team’s offensive snaps in Washington. It remains way too early to say much about Elliott’s time in Dallas, but the Cowboys’ plan to build an unstoppable rushing machine has yet to fully come together. Elliott averaged just 2.6 yards per carry in a Week 1 loss to the Giants and failed to crack 4.0 in a win over Washington last Sunday.

There’s a good chance that he’ll begin to shred defenses as rookie quarterback Dak Prescott develops, giving Elliott more time to work behind Dallas’s loaded offensive line. But in taking Elliott fourth overall, the Cowboys paid him $24.5 million guaranteed. That’s more than any other player at the position, and given what’s happening to the rest of the highest-paid backs in the league, it may stay that way for a while.

Peterson, Stewart, and Martin leaving the field on Sunday was damning for another reason: Those three happen to have the highest cap hits at the position this year, with Peterson leading the way at $12 million.

As a whole, the league’s spending habits have been in step with the notion that paying feature backs is no longer financially sound. Just 10 teams are devoting more than 5 percent of their cap to the position, and only fullbacks and snappers have a lower average salary than running backs at $1.4 million. Most rosters carry a lone punter and a kicker, but the fact that those players make more than the average tailback is astounding. The deals handed to Peterson and Stewart are outliers — Peterson’s is a product of him being the Running Back King, while Stewart’s is the last gasp of an antiquated line of thinking. Martin’s contract is brand new, and it calls into question how the league should consider the deals it gives to premier backs moving forward.

There’s no denying that Martin was among the best runners in the league last season, finishing with 1,402 yards and an average of 4.9 yards per carry. Based on the market set by Peterson and Stewart, Martin’s $8 million cap hit and $15 million guaranteed fit his production. But generally speaking, there’s a chance that NFL general managers may be better off avoiding the top-end running back market entirely.

The Bucs are fortunate: With Sims, they have a secondary option who averaged nearly 4.9 yards per carry on top of catching 51 passes last season. Spending big on a primary back has become increasingly dubious, but shelling out a little extra on a capable replacement running back makes sense. Backup quarterbacks remain part of teams’ contingency plans; backup running backs are becoming increasingly vital parts of primary plans for almost every offense in the league. Investing in a backfield with diverse skill sets is now a goal of virtually every roster in the league. In the case of Martin and Sims, it’s pretty damn nice when the third-down option is also capable of shouldering the feature back’s workload in a pinch.

Over the past couple of years, no backup running back has acquitted himself quite as well as DeAngelo Williams. The Steelers gave him a two-year, $4 million deal in March 2015, more than many starting running backs in the league make. By valuing its no. 2 runner, Pittsburgh has allowed its ground game to thrive throughout Le’Veon Bell’s suspension for violating the league’s substance abuse policy. The team has also gained some insight into how it might approach Bell’s impending 2017 free agency.

For the most part, what’s happened for the Steelers in Bell’s absence should limit his financial upside. Williams has rushed for 237 yards with two touchdowns over the first two weeks of the 2016 campaign, keeping the Steelers’ running game afloat. When Bell is on the field, he’s arguably the best back in football. In that respect, his negotiations could act as a referendum on the value of a single player at the position.

Any team negotiating with Bell will likely try to dismiss the Peterson deal as a starting point, but the fourth-year pro has a good chance to set the new market at the position (assuming Peterson is either cut or has to restructure his deal this offseason). Bell’s advantage over someone like Gordon is that he is asked to do it all for the Steelers: He may be the best pass-catching back in the league, and his talent in that area means he could stay on the field for every offensive snap, if Pittsburgh were so inclined. The question, though — especially after what we saw in Week 2 and what we have seen for the past several seasons — is whether he should play that much.

Suspensions aside, Bell has failed to finish either of the past two campaigns healthy. He hyperextended his knee against Cincinnati in Week 17 of the 2014 season; he suffered a torn MCL against those same Bengals in Week 8 last November. There’s an argument to be made that Pittsburgh’s losing him for the first three games of 2016 is actually a good thing for its Super Bowl hopes. It’s hard for that argument to hold water and for Bell to be worth the megadeal he’ll seek in the months to come.

In a football-watching world driven by fantasy interest, the death of the high-volume running back is a sad reality. So far, though, all the first two weeks of the 2016 season have reinforced is that its demise isn’t slowing down.

An earlier version of this piece wrongly identified Latavius Murray as DeMarco Murray. The piece also misstated the decline in rushing percentage from 2015 through the first two weeks of 2016; the 2015 percentage was 40.8, and it declined to 39.6. The piece also incorrectly stated that only five backs played in 75 percent of their team’s 80 games from 2011 to 2015; in fact, six backs started in 75 percent of their team’s games over that period.