The 2013 NFL draft marked the first time in 50 years that no running backs were selected in the first round.
The feature back is a dying breed.
Teams are now aiming to round out their depth charts with bevies of backs to best answer the bell in any given situation. Depending on offensive system, some of these roles are more important to one team than they are to another.
Some backs fill multiple roles, others have very specific niches. Regardless, the different types of backs all serve purposes.
The power back is as classic as a power ballad. You're headed for a heartbreak without one.
A dominant passing game can carry you down the field, but a hard-nosed running back is still vital to putting the ball in the end zone. The high-flying Patriots offense ran a league-high 60 plays from inside the opponent's five-yard line: 17 of them were passes, and 43 of them were runs. A whopping 18 of those 43 runs went for touchdowns.
So, clearly, a back who can get the tough yards in the most important spots will always have value.
You're not going to find many better one-cut backs in the NFL than Texans running back Arian Foster. The Texans offensive line has beautifully executed the zone-blocking scheme for years, but Foster's decisive running and toughness between the tackles has made him a bear for opposing defenses over the past three years.
This run against the Colts in 2010 was designed to go to the offense's right. Foster took the hand off from quarterback Matt Schaub and started to his right.
After reading the blocks, he noticed a lot of traffic in the middle and an open cutback lane.
Wide receiver Kevin Walter threw what could hardly be considered a block by diving to the ground in front of safety Melvin Bullitt, which allowed Foster to break into the second level and subsequently the third level of the defense.
Forty-two yards later, Foster had proven that a fast 40-yard dash doesn't mean the difference between a big play and a stuffed run. Sometimes, good old-fashioned vision and discipline can add up to big yards.
One-cut backs have to be able to take hits, as well, since they're not going to be untouched every time they touch the ball.
Look at Seahawks running back Marshawn Lynch, the king of after-contact yards. He's not the quickest or the fastest, but his ability to sustain hits has gained him nationwide notoriety.
His toughness is nearly unparalleled, but much of his ability to break tackles comes from incredible balance.
He found a good-enough lane to cut through, but linebackers Navorro Bowman and Aldon Smith both got hands on him. Of course, Beast Mode being Beast Mode, Lynch was able to keep his legs driving forward to pick up more yards.
He even kept moving after not one, but two more defenders tried to wrap him up.
For his efforts, Lynch piled up over 1,000 rushing yards after contact, according to ProFootballFocus.com (subscription required).
Of course, who needs good vision and cutting ability when you can just run over everyone?
Not all backs excel between the tackles. Some are at their best when they get into open space. With blockers out in front, matched up on cornerbacks, these backs are usually considered home-run threats once they get their legs moving forward.
The Titans, however, have shown how valuable a speedy back can be by drafting running back Chris Johnson in the first round of the 2008 draft. Johnson caught the eyes of scouts with the fastest 40-yard dash in combine history (4.24 seconds). His 136 runs of 20 yards or more are the second most since 2008 behind only Adrian Peterson, and Johnson's 23 rushing touchdowns of 20 yards or more are the league's highest mark in that span.
When the crease is there, and the back accelerates through it, these backs are immediately home-run threats.
Just check out this run by Chris Johnson in a 2009 game against the Texans.
The delayed shotgun hand off from quarterback Kerry Collins drew the defense into the backfield, while the offensive linemen got out in front.
Johnson just did what any smart back would do: He followed his blockers.
He turned on the jets as he made his way to the sideline and went practically untouched for a 57-yard score.
Great speed is not anywhere close to a good indicator of talent at running back. Speed is nothing without the vision to find holes, as backs will too often stutter-step in the backfield while searching for the home run.
With good speed and a talented offensive line, though, these backs can be some of the most dangerous in the NFL.
Backs who excel in the passing game are becoming more important, and more prevalent on NFL rosters.
The Bengals made North Carolina's Giovani Bernard the first back taken in the 2013 NFL draft, and while he certainly did his damage as a runner (423 career carries, 2,481 yards, 25 touchdowns), he made his presence felt in the passing game as well (92 career receptions, 852 yards, six touchdowns).
Some backs catch a lot of passes out of the backfield on dump-off plays, but others have the soft hands and the ability to run crisp routes to offer other dimensions to the passing game.
Perhaps Saints running back Darren Sproles is his own type of back altogether, but with 161 receptions for 1,377 yards and 14 touchdowns over the past two seasons, Sproles clearly takes the role of receiving back to a whole new level.
Sproles came up big for the Saints on 3rd-and-3 early in the first quarter against the Panthers. He ran a wheel route out of the backfield, with the Saints in a three-receiver set.
He tracked the ball in flight as he ran down the sideline, with the linebacker following him every step of the way.
Some backs might have lost the ball in flight, but Sproles was able to keep his eyes on the ball and extended his hands at just the right moment to make the over-the-shoulder catch.
Sproles isn't even limited to just catching passes out of the backfield, either. He can also run routes out of the slot, which creates a potential big-time matchup problem for defenses that might otherwise assign linebackers to cover him.
A receiving back adds another threat in the passing game, but some situations call for a back who can hold his own in pass protection. Backs who understand blitz pickups and can withstand oncoming defenders are ideal for this role.
According to ProFootballFocus.com, Giants running back Ahmad Bradshaw was the third-most-efficient pass-blocking running back in football last year, allowing seven total pressures on his 152 pass-block attempts.
Bradshaw (circled in yellow) lined up in protection next to quarterback Eli Manning in the shotgun. Linebacker Craig Robertson (circled in red) came on the pass-rush off the edge.
In the left frame, Bradshaw shows the ideal stance for a back in blitz protection. His feet and shoulders were square to the pass-rusher, which allowed the back to get a strong base and not to be blown off his spot.
Bradshaw lowered his head and shoulder into Robertson's midsection, allowing Manning to get the pass off before the rush got home.
Whether it's catching passes or blocking, a running back who can contribute in the passing game is a valuable component to any offense.
"The feature back is a dying breed."
That is what is written in this piece just around 1,400 words ago.
With this being said, there are still some to be found, some of whom we've even discussed in this piece.
Backs like Arian Foster, Ravens running back Ray Rice, Bears running back Matt Forte, Buccaneers running back Doug Martin, Vikings running back Adrian Peterson and others don't have to come off the field, because they can do everything for their offenses; whether it's running inside or outside, catching passes or blocking, these backs encompass all the prototypes in one neat package.
The question, then, becomes whether it's important to invest in the running-back position. Seven of the 13 running backs on the list were in the playoffs, and four of those seven won at least one playoff game.
Thus, while it may seem like the feature back is going the way of the dinosaur, you don't have to start digging in the dirt to find them just yet.
Erik Frenz is also a Patriots/AFC East writer for Boston.com. Unless otherwise noted, all stats obtained from Pro Football Focus' premium section, and all quotes obtained firsthand or via team press releases.