Speed Score 2017

by Bryan Knowles

Is the 2017 running back class the strongest in recent memory? Scouts seem to think so, projecting multiple first-round picks and plenty of depth on the back end. Only three backs (Todd Gurley, Melvin Gordon, and Ezekiel Elliott) have been taken in the first round since 2012, but 2017 has a chance to match that number.

Devoid of context, the top running backs in the 2017 draft had roughly equivalent days at the NFL Combine. LSU's Leonard Fournette, Florida State's Dalvin Cook, and Stanford's Christian McCaffrey ran within four-hundredths of a second of one another in the 40-yard dash. Speed Score, however, sees a clear winner from this year's running back crop.

Introduced on ESPN Insider back in 2008, Speed Score is Football Outsiders' metric 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 the 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.

Leonard Fournette, however, is not most running backs. Fournette weighed in at 240 pounds, and then went out and ran a 4.51-second 40. That's the fastest time for a back weighing 240-plus pounds since at least 2003, when the NFL's online records begin. It's no surprise, then, that he tops this year's table with a Speed Score of 116.0. While it's not record-setting (Georgia's Keith Marshall set the record with 126.9 last year before being drafted in the seventh round by Washington, then missing the entire season with an elbow injury), it's well above your average first-round pick's score. It also compares very favorably to Ezekiel Elliott (112.7), a comparison Fournette might have to get used to hearing. Couple his great 40 with his game tape and glowing scouting reports (a cross between Bo Jackson and Adrian Peterson, says NFL.com, exploring new depths of hyperbole), and you can see why Fournette is being touted as a top-10 pick come April.

While no one matched Fournette, most of the highly-touted backs didn't hurt themselves too much in Indianapolis. Both Dalvin Cook (103.3) and Christian McCaffrey (100.3) ended up with top-10 Speed Scores. That's below average for first-round backs, but neither is a disqualifying performance. McCaffrey, in particular, put up strong performances in the vertical jump, lateral agility drills, and receiving tests, while Cook showed off on the bench press. If teams had either player with a first-round grade coming in, they probably saw enough to keep them in the mix after the on-field workouts.

Now the caveats: Speed Score measures speed in the context of strength and power. Contrary to criticism on Twitter Saturday, Football Outsiders has never said that a larger player with a higher 40 time is actually faster than a smaller player with a lower 40 time because we are not morons. And Speed Score doesn't measure agility, receiving ability, or any of the other aspects related to playing the position. It's still correlated with NFL success, however, and it likes Fournette significantly better than the other touted backs. The 30 pounds he has on either of the other top backs matters when they're running nearly identical times. McCaffrey makes defenders miss. Fournette runs through them. Speed Score is going to like the wrecking ball over the dancer every time, and people just don't run 4.5 40s when they're as large as Fournette is.

This year's other back with a 110-plus Speed Score isn't going to go in the first round. Utah's Joe Williams ran the second-fastest 40 of the day at 4.41 seconds; at 210 pounds, that's a Speed Score of 111.0. Williams' path to the NFL is a very odd one. He was kicked out of UConn for credit card theft and illegal use before going to junior college and putting up strong numbers. He then transferred to Utah, where he actually retired from football during the 2016 season, before coming back when the Utes suffered a plethora of injuries at the position and averaging 156.3 yards per game. To say scouts are concerned about his character and his commitment to football is a massive understatement, but his on-field production and workout numbers may well be worth a late-round flier.

At the bottom of the table, we have some notably bad performances. Technically, the worst Speed Score would have gome to Virginia Tech's Sam Rogers at 78.2, but he's a fullback, and we try not to compare them directly to running backs.

Indiana's Devine Redding is a running back, however, and his Speed Score of 79.9 might bump him from a third-day pick to the undrafted free agent set. His 4.76-second 40 was slower than everyone but Rogers, and none of his other drills particularly impressed. Scouts, Inc. had him as their 24th-ranked running back coming into the combine, and an average of 20.6 running backs have been drafted per year over the last five seasons. Redding needed to stand out from the pack in order to get drafted, and while he arguably achieved that goal, it wasn't exactly in the manner one would have hoped.

Speed Score doesn't raise any huge red flags for any highly-regarded prospects. Toledo's Kareem Hunt only ran a 4.62-second 40 when he was aiming for a sub-4.5, finishing with a 94.8 Speed Score. Corey Clement (91.7) and Donnel Pumphrey (87.4) are also likely unhappy with their combine performances; both are pegged as third-day picks who might see their stocks fall after running slower than 4.6.

Among the top backs, Tennessee's Alvin Kamara put up the worst numbers, but even they weren't actually bad. He finishes with a Speed Score of 99.0 after running a 4.56-second 40, but that will likely be offset by the fact that he reportedly "crushed" the interview section -- Bucky Brooks called him the biggest combine winner in this year's running back class. Speed Score wasn't overly impressed, but it's not exactly dropping Kamara into the bust category or anything like that.

Looking at the overall class, there are plenty of solid mid-round backs available. Jeremy McNichols, Marlon Mack, Brian Hill, and Elijah McGuire all had Speed Scores over 100 and are considered mid-round picks. With a deep class, it becomes harder to justify taking a running back early, and history backs that up -- only one of the top ten leaders in rushing yards this season went in the first round. You know someone's going to be chasing the next Ezekiel Elliott, though, and Speed Score has a clear favorite. If your team goes all-in on a running back this year, hope it's Leonard Fournette.

Did not run: Justin Davis, Matt Dayes, D'Onta Foreman, Elijah Hood, De'Veon Smith