Speed Score 2019

by Bryan Knowles

The NFL Scouting combine can be a place where draft dreams are made. A great combine performance can vault someone up the draft order, giving a prospect more opportunities, more snaps and, frankly, more money than they would have received from their tape alone. It can also, however, be a place where dreams are crushed; where an apparent lack of athletic ability or poor performance on the day can send someone's draft stock spiraling.

Last year's headliner among the running backs was Saquon Barkley, who wowed us with one of the greatest combine performances we had even seen, and the fourth-best Speed Score since they introduced electronic timing back in 1999. We knew there was no Barkley in this year's class, and the consensus best running back of the year in Josh Jacobs didn't perform at the combine due to a groin injury. Still, we had a notably slow set of times: for the first time since 2014, no running back managed to top a 115 Speed Score at the combine, and a couple of decently touted prospects may have done serious damage to their draft hopes.

Created by Bill Barnwell and introduced in Pro Football Prospectus and ESPN Insider back in 2008, Speed Score is one of Football Outsiders' metrics for evaluating running back prospects. It's built on the simple idea that smaller backs tend to run faster than larger backs, so we should be more impressed by a 4.5-second 40-yard dash from a 220-pound back than the same clock reading from a 170-pound back. As such, Speed Score incorporates a back's official time in the 40-yard dash with his weight to produce a measure of his speed given his size using this formula:

The average running back who makes it to the NFL will have a Speed Score around 100, with most running back prospects falling between 85 and 110.

Speed Score measures speed in the context of strength and power. It doesn't measure agility, receiving ability, or any of the other aspects related to the position. It does not claim that a larger player with a higher 40 time is somehow faster than a smaller player with a lower 40 time thanks to the power of exponentiation. Speed Score is useful because it's beneficial for a running back to be both fast and large.

Speed Score has a higher correlation with yards, carries, and DYAR than 40-yard times alone, making it a better way to contextualize the performances at the Underwear Olympics and a better tool for finding valuable players later in the draft. It's also a part of our BackCAST projections, which combine these numbers with college production and will come out later this offseason.

Let's start with the Speed Score table, and then discuss the notable names and numbers on it.

Did not run: Rodney Anderson, Josh Jacobs, Bryce Love, Jalin Moore, L.J. Scott

The Big Names

Two of the top four running backs in the class did not run: Jacobs and Bryce Love were both nursing minor injuries, and decided to skip the running section anyway. That left Florida Atlantic's Devin Singletary and Iowa State's David Montgomery as the biggest names running. They had very similar 40 times, with just three hundredths of a second separating them. However, Speed Score shows a bigger discrepancy.

Montgomery weighed in at 222 pounds and has a nice, compact frame -- he has a more prototypical NFL size. He's certainly not considered a particularly explosive back, but a 4.63 40 at that weight isn't a terrible result -- a speed score of 96.6 is below average, but not terribly so. While he won't be beating people in the NFL with pure speed, he can create yardage for himself with his vision and instincts, and he has enough speed and mass to power through hits. He was considered a solid Day 2 back coming in, and didn't do much to hurt his stock.

Singletary was only a tick slower at 4.66, but he only weighed in at 203 pounds! There are small running backs who had success in 2018 in the NFL -- Christian McCaffrey weighed in at 202 and had nearly 1,100 yards last season, and Marlon Mack and Tevin Coleman also had solid seasons at small weights. But McCaffrey ran a 4.48 at his combine, Mack had a 4.50 and even Coleman managed to squeak out a 4.59. Singletary's Speed Score clocks in at just 86.1, and that has to be a red flag for evaluators. An undersized back like Singletary needs to be elusive and quick in order to be productive, because he's not going to run people over. A 4.66 is not the sort of speed you hope to see out of a back that size, and that drops him below the dreaded Ahmad Bradshaw Line.

The Ahmad Bradshaw Line

Speed Score doesn't guarantee anything, of course, but the higher your score, the better career you generally have. You can see the production of backs fall off as Speed Score drops off in this table:

Updated Speed Score track record, 1999-2014.

X% of players with a Speed Score of Y go on to average Z yards per season.

Be big, be fast, or be Arian Foster. pic.twitter.com/BG1vW05oUd

— Bryan Knowles (@BryKno) March 1, 2019

There are exceptions to every rule. Arian Foster had a Speed Score of 94.2, but still topped 5,000 yards in his first five years -- he's that "1.4 percent" on the chart, the only running back with a Speed Score under 100.0 who managed to average a thousand yards a season for five years. So, no, a low Speed Score doesn't mean you're guaranteed to be a bust. But…

Ahmad Bradshaw holds the record for worst Speed Score for a productive running back. Back in 2007, Bradshaw ran a 4.61 40 at 198 pounds, for a Speed Score of 87.7. Only one player below that score even managed 1,000 yards in their first five seasons, and most of them washed out of the league after a year or two. That's the low-water mark; an athletic point of no return. If Singletary turns into a successful NFL back, he will be bucking all modern statistical trends.

Singletary did not have the lowest Speed Score of the year, however. Wisconsin's Alex Ingold is a fullback, and thus his Speed Score isn't particularly relevant. LSU's Nick Brossette is a seventh-round prospect who may have bumped himself down into UDFA territory with his combine performance. Then, we get to Georgia's Elijah Holyfield.

Holyfield managed a 4.78 40-yard dash on his first attempt. To put into context, Da'Shawn Hand, defensive tackle for the Detroit Lions, managed a 4.83 at the combine last year. When you have trouble outrunning defensive tackles, you're not going to have a great 40 time. You do get two runs, however, and on his second run, Holyfield could only manage a 4.81. That's a fine time for an Ironhead Heyward or a Le'Ron McClain, basically a bowling ball you crash into the line. But Holyfield isn't that type of player -- he weighed in at just 217 pounds, which is more Joe Mixon or Adrian Peterson size. That's a Speed Score of just 83.1; Elijah's dad Evander had knockouts that happened quicker than Elijah ran the 40.

Before the combine, there was talk of Holyfield sliding up in to the second day thanks to his stout frame and aggressive rushing style, but he just looked like he was running through molasses out there. He has a lot riding on his Pro Day now to show that this was some kind of fluke; it was one of the worst 25 Speed Scores we've ever recorded, including fullbacks.

Standout Performers

Not everyone had a terrible performance in the 40, mind you. There may not have been a Barkley or a Leonard Fournette, but one player did get into the 110s: Temple's Ryquell Armstead, who opened the day with a 111.2 Speed Score. Armstead is a late-round flyer without the lengthy college track record to support him -- he didn't break into Temple's starting lineup until he was a senior, and struggled with injuries. Still, his 4.45-second 40 was the second-fastest time of the day, and doing it at 220 pounds should at least cause teams to give his physical running style another look, and probably will make sure he gets his named called at some point during the 2019 draft.

A 111.2 score is the lowest high-water mark we've seen in the electronic timing era, beating out Jerious Norwood's combine-leading 112.1 back in 2006. This is not a top-heavy class of running backs.

Most of the other backs over 100.0 are also lightly regarded prospects and mid- to late-round flyers. Mike Weber and Justice Hill are ranked around 190th on the current Scouts Inc draft board, though that might go up after Speed Scores over 105.0. Darrell Henderson of Memphis briefly topped the Speed Score rankings with a hand-timed 4.37; the electronic timing knocked him down by more than a tenth of a second, however, turning a great score into just an above-average one.

Of the highly regarded backs, perhaps Penn State's Miles Sanders had the best day. His Speed Score of 103.8 isn't anything to scoff at, and he had a great performance in some of the other drills as well. He was docked some in scouting reports for average acceleration, but he showed that he can turn on the jets when need be, putting up a very good 4.49 40 and showing off some change-of-direction skills in the following drills. For the second year in a row, your combine winner at running back might just be a Nittany Lion, even if Sanders pales in comparison to Barkley's day a year ago.