The debate about the importance of running backs can and will wage on for years. It's really just beginning.
The discourse on the value of running backs trickles directly into the NFL Draft. Now, generational talents can still be viewed as poor investments at the top of the board because of the position's impact on NFL success.
But, hey, who cares about all that? I don't. Not for this article at least. This isn't the article to stoke that fire.
The fact of the matter is that running backs are going to be drafted in April and are going to carry the ball in an NFL uniform. And that's fine. League-wide rushing efficiency ticked up this season at the NFL level based on our advanced metrics at numberFire, and backs will always have a place in pro football.
But which incoming prospects were the most efficient rushers in 2018? That's also a tough nut to crack.
When we dig into the college game to try to figure out rushing efficiency, it's quite hard contextualize, as offensive philosophies vary greatly across college football. But that doesn't mean we can't try to dig a bit deeper than sheer yards per carry to see which running backs invited to the NFL Combine were the most efficient -- compared to their teammates -- in 2018.
The Process
While we at numberFire generate success rates at the NFL level based on whether or not a play increases expected scoring according to our Net Expected Points metric, we can't replicate that expected-points approach at the NCAA level.
Instead, I've combined collegiate play-by-play data and applied the FootballOutsiders' success rate methodology to determine success rates, based on necessary yardage to gain a first down on each carry that a running back saw.
However, rather than relying solely on individual success rates, which can be heavily influenced by team success, situation, and overall offensive philosophy, I have also derived the success rate of the teammates of each combine-invited running back in order to find levels of separation from teammates. This should help level the playing field and shed light on which backs were efficient within their own situations while eliminating generally more efficient quarterback carries.
This should, in theory, do a few things and add some clarity into some possible situations.
One such example could be making a back with an average success rate look better if his teammates struggled in the same offense. Another could make an average success rate look less impressive if all teammates thrived in an elite rushing offense.
I think two examples are enough.
The Results
Let's dump all the data here and then dive into what it may mean for some of the most intriguing prospects. Keep in mind that none of this is going to be a singular sticking point for or against any player. It's just meant to delve into contextualized rushing efficiency.
The table below includes: team rushing efficiency ranks according to FootballOutsiders' S&P+, a back's success rate, the success rate of his running back teammates, and the differential between the two.
(Note: Rodney Anderson of Oklahoma saw only 11 carries in 2018, so his 2017 data is used.)
| Rusher | Team | Rush O Rank | Success Rate | Teammate Success Rate | Diff. |
|---|---|---|---|---|---|
| David Montgomery | Iowa State | 102 | 39.0% | 25.4% | 13.7% |
| Ryquell Armstead | Temple | 82 | 41.9% | 32.5% | 9.4% |
| Alexander Mattison | Boise State | 14 | 41.1% | 32.2% | 8.9% |
| Karan Higdon | Michigan | 38 | 39.7% | 31.4% | 8.3% |
| Josh Jacobs | Alabama | 2 | 55.8% | 47.6% | 8.3% |
| Dexter Williams | Notre Dame | 72 | 39.5% | 32.1% | 7.3% |
| Alex Barnes | Kansas State | 58 | 39.1% | 32.1% | 6.9% |
| Elijah Holyfield | Georgia | 10 | 48.1% | 42.4% | 5.7% |
| Tony Pollard | Memphis | 5 | 49.4% | 45.9% | 3.5% |
| Bryce Love | Stanford | 107 | 30.5% | 28.1% | 2.3% |
| Mike Weber | Ohio State | 54 | 44.4% | 42.2% | 2.2% |
| Jalin Moore | Appalachian State | 56 | 36.5% | 34.8% | 1.7% |
| Darrell Henderson | Memphis | 5 | 46.7% | 46.3% | 0.4% |
| James Williams | Washington State | 51 | 42.6% | 43.0% | -0.4% |
| Rodney Anderson* | Oklahoma | 1 | 42.0% | 42.6% | -0.6% |
| Benny Snell Jr. | Kentucky | 52 | 39.5% | 41.9% | -2.4% |
| Nick Brossette | LSU | 81 | 35.4% | 39.1% | -3.6% |
| Damien Harris | Alabama | 2 | 46.7% | 51.3% | -4.7% |
| Jordan Scarlett | Florida | 20 | 42.0% | 46.8% | -4.8% |
| Myles Gaskin | Washington | 34 | 36.2% | 41.4% | -5.2% |
| LJ Scott | Michigan State | 112 | 26.6% | 32.5% | -5.9% |
| Justice Hill | Oklahoma State | 27 | 36.9% | 43.1% | -6.1% |
| Trayveon Williams | Texas A&M | 16 | 42.8% | 50.0% | -7.2% |
| Qadree Ollison | Pittsburgh | 11 | 37.3% | 44.6% | -7.3% |
| Travis Homer | Miami-FL | 45 | 34.0% | 41.8% | -7.8% |
| Miles Sanders | Penn State | 17 | 41.3% | 52.6% | -11.3% |
| Devin Singletary | Florida Atlantic | 30 | 35.7% | 51.5% | -15.8% |
At the Top
At the top of the list is David Montgomery from Iowa State, who also just -- in general -- produced like a stud. Montgomery's 39.0% rushing success rate would have ranked him 18th among the 27 backs here, but the team-dependent context can help us. The Cyclones ranked poorly in overall rushing efficiency (102nd in Rushing S&P+), but Montgomery (obviously) outperformed his running back teammates greatly. Montgomery grades out as a top-five running back prospect after accounting for production, size, projected athleticism, and projected draft stock, according to my draft model.
Ryquell Armstead from Temple is a similar case to Montgomery from an efficiency standpoint, albeit a very different level of prospect. Like Montgomery, Armstead played in a modest rushing offense in 2018 but had a sizable gap in success rate over his fellow Owl running backs. Armstead projects as an undrafted pick despite his senior season, and he totaled 29 receptions in four seasons.
Alexander Mattison is yet another prospect without much in the way of draft equity despite an efficient rushing season at Boise State in 2018. He grades out near the 50th percentile in a lot of measurables. Mattison, though, handled roughly 40% of the Broncos' touches this season, ranking him fourth among combine-invited backs, and that receiving ability in addition to the rushing numbers can help him find a home at the next level.
Karan Higdon grades out as a back-half-of-the-draft option who didn't account for much in the way of receiving at Michigan. However, Higdon did manage a top-10 rushing market share among the backs at the combine despite weighing in at just 205 pounds.
Now back to a bigger name and possibly the biggest in the draft class: Josh Jacobs. Jacobs split touches with Damien Harris and Najee Harris at Alabama this past season. Jacobs notched the best rushing success rate of any backs at the combine this year, which should tell us a lot, given his difficult schedule. However, he also was part of the second-best rushing offense in football by S&P+, so the fact that he outperformed his teammates within that offense is just as impressive and helps us overlook a relative lack of production within his own offense. Damien Harris, by comparison, ranked fifth in the combine-invited class in success rate but wasn't quite as efficient as Jacobs and Najee Harris.
Dexter Williams doesn't do too much to separate himself from the pack, which helps explain the fifth-round-or-later projected draft stock he generally has, and posted just a mid-level reception share to go along with efficient rushing. Still, the Notre Dame alum grades out seventh in dominator rating among his combine peers.
Alex Barnes led all backs in dominator rating while at Kansas State this past season and paired that with some strong relative efficiency. The productive Wildcat, however, didn't break out early on in his career.
Elijah Holyfield tallied 1,018 yards and 7 touchdowns on 159 carries at Georgia while running alongside D'Andre Swift (1,049 yards and 10 scores on 163 carries). Holyfield, though, notched a 48.1% success rate, compared to 43.6% for Swift.
Tony Pollard is forgoing his senior season at Memphis after rushing 17 times for 109 yards and a touchdown in a bowl game, which teammate Darrell Henderson elected to miss. Albeit on 79 carries (compared to 214 for Henderson and 204 for Patrick Taylor Jr.), Pollard secured the best success rate of the three (49.4% compared to 46.7% for Henderson and 46.1% for Taylor Jr.). Pollard's receiving ability (second in the class in reception market share) could allow him to be a versatile player at the next level.
Near the Bottom
Devin Singletary is shaping up as a potential Day 2 pick by some mock drafts, though he measured up quite small at 5'7.5" and 203 pounds. Despite the diminutive size, Singletary accounted for the second-lowest rate of receptions among this combine's backs in 2018.
Miles Sanders, conversely, ranked fourth in reception market share and is bigger than Singletary (5'10.5", 211 pounds). I've seen projections for Sanders from the fourth round to undrafted. He had an underwhelming touchdown share in 2018 and lacks an elite breakout age (though he played behind Saquon Barkley).
Trayveon Williams, a personal favorite of mine, churned out elite yardage totals and ranks third in dominator rating among the combine class. At 5'8", 206 pounds, Williams doesn't profile as an every-down back at the NFL level, despite being that at Texas A&M. He ranks fifth in reception market share to help account for the disappointing rushing efficiency.