The 2022 Vikings 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 can be found here.
I’ll start by taking a quick overview of each team’s raw rushing volume and propensity to run the ball. Then, I’ll dive into the player evaluation portion. Before we start, let’s define the metrics I’ll use as part of those evaluations:
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.
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.
Measures the disparity between a running back’s percentile ranks in BAE Rating and RSR in order to indicate how volatile a player’s per-carry performance is. High overall efficiency paired with low rate of success indicates boom/bust output, while low overall efficiency paired with high rate of success indicates steady, low-ceiling output. Measures degree of volatility, not quality of performance.
Composite Efficiency Score (CES)
Presents a single-metric overview of the quality of team-relative performance a player produced on his carries in a single season. Calculated using the average of a player’s percentile ranks in Box-Adjusted Efficiency Rating and Relative Success Rate, represents player performance on a 0-100 scale.
Team Rushing Volume
The Minnesota Vikings finished an even No. 16 in the NFL last year in rushing attempts in 2021. Their 449 total were just three shy of the league average. Klint Kubiak served as the offensive coordinator in Minnesota last season. However, the Vikings finished No. 8, No. 4, No. 27, and No. 2, respectively, in the same category under four different offensive coordinators in the previous four years. With Kubiak and former head coach Mike Zimmer now out of the picture, things should look different in Minnesota.
New head man Kevin O’Connell brings Wes Phillips with him from Los Angeles to coordinate the Vikings offense. With the Rams, they served as Sean McVay’s offensive coordinator and passing game coordinator, respectively.
According to rbsdm.com, the Vikings ranked No. 14 in the NFL in early-down run rate in neutral game script situations (when win probability for either team did not exceed 80-percent) last season. Conversely, O’Connell’s Rams were the No. 4-most pass-happy team in the league in 2020 and 2021.
The Vikings were also relatively run-heavy in most down-and-distance situations last season. They ran the ball 2-percent more often than expected (given league-wide play-by-play data) overall. On the other hand, the Rams threw the ball 3-percent more often than expected.
We should expect the Vikings to have a more modern and pass-oriented offense under the oversight of O’Connell and Phillips. If the Rams are any indication, that will mean less rushing volume but more offensive efficiency overall.
Dalvin Cook was the lead man in the Minnesota backfield in 2021. Alexander Mattison served as the clear number two for the third year in a row. Behind them, Kene Nwangwu and Ameer Abdullah handled spot duty. Here are the full rushing efficiency profiles for each of those four backs:
Cook was great last year. Among 122 running backs who had at least 10 carries in 2021, his Composite Efficiency Score ranked No. 18 overall and was No. 6 among lead runners. He has posted a positive Relative Success Rate and CES above the 60.0 mark in every season of his career. Cook turns 27 in August, and despite yearly injuries, he shows no signs of slowing down.
Mattison posted the worst performance of his young career from an efficiency standpoint last season. His Box-Adjusted Efficiency Rating was the lowest in the NFL among players with at least 100 carries. While competing with Cook for team-relative efficiency means Mattison has a tougher road than most to posting quality numbers, he managed quality BAE Ratings of 99.6-percent and 102.5-percent in his first two seasons, respectively. He was bad last year.
Nwangwu and Abdullah didn’t touch the ball enough to evaluate properly. However, Nwangwu’s volatile-but-efficient output tracks with his reputation as a dynamic but raw athlete.
So Now What?
Cook didn’t score a lot of touchdowns a year ago. However, he might’ve had his best season on the ground from a per-carry perspective. He remains one of the bet pure runners in the league. Cook should be a near-elite RB1 in fantasy for 2022. As part of a cohort of older but productive backs that are being selected in back-end RB1 territory in dynasty, he’s a relatively affordable win-now asset.
Mattison is what he is. He’s (probably) not terrible, but he’s also not good. He is a three-down blah back who will be a fringe RB1 whenever Cook misses games as part of his yearly quota of three or four inactive contests. I wouldn’t bet on it. I also wouldn’t shocked me if one of fifth-round rookie Ty Chandler or UDFA Bryant Koback end up having more juice than Mattison and are able to surpass him on this depth chart.
The only other back on the roster is Nwangwu. Nwangwu is likely in the mix with Chandler and Koback. If I were ranking them based purely on my own estimation of their talent, I’d go Koback, Chandler, Nwangwu, but that also might be the straight inverse of how the battle for roster spots ends up shaking out.
At some point the injuries will catch up to Cook, but he’s a stud every time he’s on the field. I also don’t make decisions based on hypothetical Schrodinger’s cat outcomes. He’s palatably priced and will give you elite production any time he’s active.
Mattison is more valuable to the Cook owner in your league than he is to anyone else, and I’d be content to slot him into my RB2 spot three times a year unless that guy or gal is willing to overpay.
Outside of those two, I’m taking late shots on Koback as a low-key three-down beast with a lot of athletic juice.