clock menu more-arrow no yes mobile

Filed under:

RBs have a lower expected return when drafted early compared to other positions

NFL: AFC Championship-Jacksonville Jaguars at New England Patriots David Butler II-USA TODAY Sports

Friday Field Gulls author Ben Baldwin published a fantastic piece listing several reasons why running backs in the modern NFL are not worth a team spending a top 20 pick on. There was considerable pushback on this idea from many fans, arguing of the success the Dallas Cowboys had in 2016 following the drafting of Ezekiel Elliott, and the 2017 success of the Jacksonville Jaguars after drafting Leonard Fournette. However, while both of those teams found success after drafting a running back with the fourth overall pick, the reasons for their success went far beyond the running back the team had selected.

Today I’m going to look at just one of the points that Ben mentioned in his article, which is the following:

In particular, we’ll be taking a business school approach to this question in evaluating NFL players as assets of a business. Is that cold and heartless? Yes, and I don’t mean to diminish what NFL players do in any way, but this is how the guys in the finance office look at any employee of any company. So, the next time someone from management says employees are the most valuable asset of the company you work for, don’t roll your eyes and think, “oh great, more management speak”. Instead, think, “holy cow, these guys look at us like they look at every other depreciable, replaceable asset in the company like desks and computers”. Using more management speak, it is what it is, and to companies employees are nothing more than assets with useful life expectancies, depreciating values and replacement costs. Whether someone is a football player, a writer, an accountant, a doctor or anything else, at the end of the day they are an asset that plays a role in generating excess value beyond cost for their employer.

However, back to the topic at hand rather than the fact that humans are no more than cogs in the machine. Ben notes that running backs have short shelf lives, so let’s evaluate the expected shelf life of running backs taken with picks one through twenty in the draft and see where they rank. Here’s a table with the data for every player drafted by an NFL team between 1970 and 2007 for the different position groups.

Career expectations by position for players drafted 1.1 to 1.20 from 1970 to 2007

Position Games (mean) Games Started (mean) AV (mean) Games Started (median) AV (median)
Position Games (mean) Games Started (mean) AV (mean) Games Started (median) AV (median)
QB 106.4 95.1 55.6 94 56
RB 100 68.9 44.5 61 38
WR 115.5 87.6 44.5 73 38
TE 118 94 29.5 87 24
OL 129.3 114.7 51.7 110 47
DL 120.5 94.2 45 90 42
LB 125.1 102.4 50.7 102 47
DB 123.9 104.8 47 109 47
All data on drafted players collected using pro-football-reference.com

What we see is that running backs drafted at the top of the first round do indeed have shorter expected careers by games played and games started compared to the other positions. Further, they also have a lower expected career AV relative to other position groups, with the exception of tight ends and wide receivers. Tight ends fall far below every other position when looking at return on investment from an AV perspective, with running backs and wide receivers right behind them.

In order to check whether the results of these picks might have also been top heavy, pulling the means higher, I also included the median for Games Started and AV for each position group. It made a difference in a few of the position groups, but no difference in others. Running backs and wide receivers saw the biggest point gap (6.5) between the mean and median AV values, while tight ends had the biggest percentage gap (18.6%). This makes sense, as the top performers in these categories pulled the mean production up drastically.

For running backs, nearly two thirds of all the production in rushing yards and touchdowns scored came from the top third of running backs drafted. For example, the top third most productive running backs had mean production of 9,837 rushing yards and 72 touchdowns for their careers, while the middle third averaged 3,849 rushing yards and 25 touchdowns. Those who fell into the bottom third in terms of least productive during their careers averaged just 1,457 yards and 10 touchdowns.

What that means is that if the Seattle Seahawks use pick 1.18 in April on a running back, there’s roughly a one in three chance that the player they select with end their career with production that falls roughly in line with what Marshawn Lynch averaged per season from 2011 to 2014 (1,339 yards and 12 touchdowns).

In addition to shorter expected careers, running backs are more likely to miss time compared to other positions according to studies such as this one from ProFootballLogic.com. That study found that the injury risks for running backs is higher than any other position. Of all position groups, running backs are most likely to have both a higher probability of suffering an injury in any given game as well as having any injury a running back suffers likely to result in a higher number of missed games. That leads to running backs being the position that has the lowest expected availability over the course of a season, as is seen in this table from the study.

A great data set courtesy of ProFootballLogic.com

Thus, running backs are the most likely to miss time during any given game, and they are the position that is likely to have the shortest career.

Turning back to our business school analysis of football players as assets, one of the first lessons learned in any Intro to Finance class is to calculate Net Present Value (NPV). I’m not going to get into the fine details of either of those, as the short version will suffice, and that is that the value of any asset that is being evaluated for acquisition is the present day value of all the future value provided by the asset.

With running backs having the shortest expected careers of any position group when drafted in the top twenty picks, as well as one of the lowest expected career AVs of any position group, that makes the position one of the least desirable on which to spend significant draft capital.

From a decision making standpoint, drafting a running back early simply does not make sense. It’s like being presented with a series of slot machines all in a row, and the running back and wide receiver slot machines possessing the second lowest payout ratios. In contrast, the machines for offensive linemen, linebackers and defensive backs have higher payout ratios.

Interestingly, the only players the Seahawks have drafted in the top twenty during the Pete Carroll and John Schneider era have been an offensive lineman (Russell Okung), a defensive back (Earl Thomas) and a linebacker (Bruce Irvin). Three picks is obviously a small sample size, but it is certainly interesting that all three fall into three of the categories which would rank the highest under this extremely rudimentary overview.

However, digging deeper into the team’s draft history and the general probabilities for success in the draft are different subjects for a different day. With the legal tampering period of free agency starting just two weeks from Monday, there are more pressing subjects to be covered in the coming days. Thus, we’ll simply leave off on the fact that running backs selected in the first twenty picks are likely to generate less value for a team relative to other positions.