The 2022 Steelers Backfield Breakdown is part of an offseason series in which I take a deep dive into one NFL team’s backfield and examine the respective rushing performances of the players in it. In doing so, I hope to gain insights into key players from a talent evaluation standpoint, and using that evaluation as a baseline, from a dynasty valuation standpoint. The first installments in the series covered the Patriots, Lions, Titans, and Steelers.
I’ll start by taking a quick overview of each team’s raw rushing volume and propensity to run the ball in general, and then dive into the player evaluation portion. Before we start, let’s define the metrics I’ll use as part of those evaluations:
Key Metrics
Yards per Carry+ (or YPC+)
The degree to which a player’s raw yard per carry average exceeds or falls short of the collective yard per carry average of all other running backs on his team. Meant to be an overview of a player’s team-relative efficiency.
Box Count+
The degree to which the average amount of defenders in the box that a player faces on his runs exceeds or falls short of the collective average faced by the other running backs on his team. Considering that the outcome of any given rushing attempt is largely dependent on the amount of defenders in the box pre-snap, Box Count+ describes the relative degree of difficulty of a running back’s carries.
Breakaway Conversion Rate (BCR)
Quantifies performance in the open field by measuring how often a player turns his chunk runs of at least 10 yards into breakaway gains of at least 20 yards.
Box-Adjusted Efficiency Rating (BAE Rating)
Improves upon YPC+ by accounting for the box counts that a player carried the ball against. Looks at team-relative yards per carry against each individual box count, then uses a weighted average (based on total carries against each box count) to generate an overall score. A score of 100-percent indicates that a player is producing exactly the per carry output of his teammates, a score above 100-percent indicates that he is outdoing their per carry output to whatever degree, and vice versa for a score below 100-percent.
Relative Success Rate (RSR)
Measures player consistency using Success Rate, but relative to his teammates and adjusted for the box counts that he faced in the same way that BAE Rating is. “Success” on a given carry is defined by gaining 40-percent of yards needed on first down, 70-percent of yards needed on second down, and 100-percent of yards needed on third or fourth down. A score of 0.0-percent indicates that a player is succeeding on exactly the same percentage of his carries as are the other backs on his team, a positive score indicates that he is succeeding more often than his teammates are, and vice versa for a negative score.
Team Rushing Volume
The Arizona Cardinals ran the ball 496 times in 2021; the seventh-highest carry total in the league and more than 40 greater than the league average. Last season marks the second year in a row in which the Cardinals were near the top of the league in rushing attempts; they ranked No. 6 in 2020.
Much of that run-heaviness is due to Kyler Murray‘s propensity to take off from the quarterback position. Wide receiver Rondale Moore also added 18 carries last year. And Arizona was just near league average when only counting rushing attempts by running backs.
Regardless of who is carrying the ball, Kliff Kingsbury is calling running plays fairly often. According to rbsdm.com, Arizona was No. 9 in the league last season in rush rate in early-down and neutral Game Script situations (when win probability for either team did not exceed 80-percent). They were No. 12 in the same metric in 2020. On aggregate, they called situational run plays right at the expected rate based on league-wide play-by-play data. But they were run-heavy on 1st-and-10 and in most short-yardage situations.
For the purposes of evaluating and projecting running back performance, the Cardinals are pretty run-of-the-mill as far as rushing volume goes.
Efficiency Numbers
It was mostly a two-man show with James Conner and Chase Edmonds in the Cardinals backfield last year. But Eno Benjamin and Jonathan Ward both handled some spot duty. Here are the full rushing efficiency profiles for each of those four guys:
Easily the best runner among Cards running backs was Edmonds. He was significantly more efficient than the other backs on the team while seeing the heaviest box counts among them. His great efficiency was also not just fueled by big plays; his Breakaway Conversion Rate is just a 48th-percentile mark. Further, he was more consistent than his counterparts, as evidenced by the positive Relative Success Rate he posted.
Benjamin and Ward were both relatively inconsistent on limited work. Benjamin was also inefficient, but given the box counts he saw, Ward was tremendous on his nine carries.
On the other hand, Conner was not good as the lead runner. Largely due to his performance in short-yardage and other obvious running situations, he posted a quality Relative Success Rate, but he was pretty bad otherwise. His YPC+ is in the 15th-percentile. Given his basically seeing the same box counts as the team’s other backs, there’s not much excuse for his inefficiency. The Box-Adjusted Efficiency Rating he posted is a 21st-percentile mark; the lowest in the entire league among backs who led their teams in attempts.
So Now What?
Chase Edmonds and James Conner both entered the free agent market this offseason. In my opinion, the Cardinals kept the wrong guy. They brought back Conner while Edmonds signed a deal with the Miami Dolphins. Right now, it looks like it’ll be the Conner and Benjamin show in Arizona in 2022.
Projecting Conner going forward is interesting because 2021 was really the first time in his career that he’s been an inefficient runner relative to his teammates. He had positive BAE Ratings and Relative Success Rates in every one of his seasons in Pittsburgh. And he’s posted a BAE Rating above the 90th-percentile as recently as 2020.
As far as evaluating Conner in a vacuum goes, I can see things going one of two ways. The first possibility is that 2021 was an aberration where he happened to lag behind a dynamic runner in Edmonds, and will be otherwise fine going forward. The second is that, like many backs before him, Conner simply fell off the age cliff and is now toast.
For my money, I’ll bet against the 27-year old running back who just posted by far the least efficient campaign of his career having a bounce back season.
Final Word
Despite abysmal efficiency, James Conner finished 2021 as the RB5 in PPR. He was able to accomplish that feat because, while having fewer touches than all but two of the other top-12 running backs, he scored the third-most touchdowns of any runner in the league.
A bet on Conner as a high-end fantasy option in 2022 is a bet on two unlikely developments coming to fruition at once. The first is on his having an elite touchdown rate in back-to-back seasons. The second is on his bucking the trend of running backs over the 25-year mark suddenly losing their effectiveness and then fading into the ether.
Neither of those are bets I’m willing to make on their own, and I’m certainly not going to parlay them. A better wager would be on Eno Benjamin, a guy who was both productive and efficient in college, to bounce back from a disappointing small-sample rookie year and play well in the RB2 role.
Another better wager would be on Chase Edmonds to impress in Miami, but that’s a story for another time.
