2022 Steelers Backfield Breakdown: Najee Harris Mythbusters

by Noah Hills · Analytics & Advanced Metrics

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, on the Patriots, Lions, and Titans 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 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

With only 411 rushing attempts in 2021, the Steelers posted their second straight season (and third in four years) in the bottom five of the league in carry volume. They had over 40 carries fewer than the league average.

Those low carry totals were not just a result of being involved in shootouts or trailing late in games. According to rbsdm.com, Pittsburgh had the fourth-lowest run rate in early down, neutral Game Script situations (when win probability for either team did not exceed 80-percent) last year. They also opted to throw the ball more than expected (based on league-wide play-by-play data) in most down-and-distance situations. Especially in short yardage.

The Steelers are simply a pass-happy team in general. Perhaps that inclination has been due to their relatively poor run-blocking offensive line. Perhaps it has been due to their trust in the hallowed husk of future Hall of Famer Ben Roethlisberger. Or perhaps its just what they want to do on offense. Roethlisberger is gone, Mitchell Trubisky (or maybe a rookie?) is in at quarterback. And more changes are sure to come for the Steelers offensive personnel. Maybe, maybe, we’ll see some shift in play-calling and overall philosophy as a result. However, this pass-heavy approach is something we’ve seen for years now in Pittsburgh. So it seems unlikely that they’d swing their pendulum fully toward a high-volume rushing attack.

Efficiency Numbers

The Steelers running game was one of the more monopolized in the league last season. But there were still four running backs who took handoffs. Here are those runners — Najee Harris, Benny Snell, Kalen Ballage, and Anthony McFarland — and their full 2021 rushing efficiency profiles:

Let’s interpret the reading rainbow here.

To get McFarland out of the way: he played in two games, carried the ball three times, and totaled one yard. He was hurt, but this was a disappointing sophomore campaign to follow up a disappointing freshman campaign from a player that way too many people were in on in rookie drafts two years ago.

The contributions of Snell and Ballage were nearly identical. They both were far less efficient and far less consistent than the collective other backs on the team; which essentially boils down to 307 carries from Harris plus the contributions of their counterpart. They both averaged fewer yards per carry than Harris did while seeing lighter box counts than he faced. And neither of them managed to rip off even a single breakaway run.

Harris’ carries represent a massive 74.7-percent share of the team’s total rushing attempts. He was easily deserving of that volume given his performance relative to the other backs on the team. The monopoly he had on this rushing attack does make a team-relative evaluation of his efficiency numbers a bit more difficult than it is for players in more evenly distributed backfields. But Harris’ situation isn’t completely unique.

The Workhorse

I haven’t collected data on every team yet. Of the 21 teams I do have numbers for, Najee Harris is joined by Joe Mixon and Jonathan Taylor as lead runners who saw their collective backups total fewer than 100 carries.

Of those three workhorse backs, Harris saw the highest relative box counts. He posted the highest Box-Adjusted Efficiency Rating, and had the highest Relative Success Rate. You could (probably successfully) argue that the ancillary runners for the Steelers are worse than those for the Bengals and Colts. But these guys are all talented players who were excellent in college and have earned work in the NFL. Outdoing them to any degree is fairly impressive. And the degree to which Harris outdid his backfield mates was massive.

So Now What?

Ten months ago, the post-NFL Draft sentiment around the Steelers landing spot for Najee Harris was that he’d certainly get a lot of touches but that his productivity would suffer due to the Steelers porous offensive line. Fast forward to the end of the 2021 season. Harris did get a lot of touches, the most in the league, in fact. But his productivity was just fine. He finished as the RB3 in season-long PPR points (and he was RB8 in points per game).

Bafflingly, the detractors are now pointing to a lack of efficiency as a reason to fade Harris going forward. To recap:

  • Harris gets drafted to a team we know to have a horrible offensive line.
  • Harris is inefficient relative to a bunch of players on other teams (largely) without horrible offensive lines (and he was: among 50 running backs with at least 100 carries last season, Harris ranked No. 38 in yards per carry).
  • Because of point No. 2, Harris is bad and you should fade him.

Make It Make Sense

We knew the Steelers line would be bad and we knew Harris would be inefficient because of it. Why are we now amending our evaluation of Harris to account for the fact that he was inefficient? Especially when that inefficiency had very little to do with him? Further, it’s impressive he rose above what was offered to him by the offensive line to the degree he did. Especially considering his tremendous team-relative efficiency numbers. If anything, we should like Harris more now than we did a year ago, not less.

Still unconvinced? The last piece of evidence I would like to present in favor of Harris not being terrible is his team-relative rushing efficiency profile from his time at Alabama:

Box count data is not available for Harris’ freshman year. But his 61 carries from that 2017 season represent less than 10-percent of his career total. The rest of the time, he was outpacing college backfield teammates that are surely more talented than his current Steeler counterparts. Including Josh Jacobs, Damien Harris, Jerome Ford, and Brian Robinson. Did he become worse in 2021 because his raw yards per carry in the NFL hasn’t been good? Or is he the same great player but now in a situation not conducive to efficient play? I suppose you can decide that for yourself.

Final Word

Leave the Stone Age. Stop citing Najee Harris‘ low raw efficiency numbers as a reason why he was overrated as a prospect or should be faded in dynasty. He was a great player in college and he’s a great player now, from both productivity and efficiency standpoints.