Drafting Running Backs

On Wednesday afternoon on 950 KJR Softy Mahler was talking about all the quality college running backs that are available in the NFL draft this year. That got me thinking about the success NFL teams actually have in drafting rushers. Over the last several years the conventional wisdom has settled on the idea that only the most outstanding can't miss running backs should ever be taken first round of the draft and even those guys should probably be in the second round. The reason being the position is very dependent on the play calling of the coaches and the blocking of the offensive linemen. Very few athletes are able to be game changers without a high quality group of linemen in front of them. So teams should focus on blockers and then find someone to run behind them. Additionally running back is a position with high risk of injury so investing a lot of resources into the position doesn't have a high enough potential return. I wanted to know if this thinking is actually playing out with the players being drafted at running back. Then on Thursday the Seahawks went and took Rashaad Penny from San Diego State University with the 27th pick of the first round and I really had to know.

During the five seasons between 2013 and 2017 there were 54 instances where an individual player rushed for 1000 or more yards (see Figure 1). 34 different players recorded one of those 54 seasons. The distribution of the round the player was drafted in looked pretty conventional with the 1st round being the most common followed by the second round and so on. Figure 1 shows the distribution. Interesting there were 4 seasons where a player that recorded 1000 yards rushing was an undrafted free agent. C.J. Anderson, LeGarrette Blount, Chris Ivory, and Arian Foster are the four men that achieved this feat. This data points towards that conclusion that a player that records a 1000 yard season is more likely to have been drafted highly. However, this doesn't tell the whole story. If there are just a few highly skilled first rounders continuously racking up big yardage seasons it would skew he data. It could be that a high percentage of 1st rounders never pan out then actually perform well in the NFL.

Figure 1: Running Backs to rush for 1000 yards are more likely to have been drafted in the earlier rounds.

I looked at all the running backs drafted between 2013 and 2017. A total of 122 running backs were drafted over the course of the five drafts. On average 24 running backs were taken in the draft. The high was 2017 when 30 running backs were taken and the low was 2014 when only 21 were taken. Assuming that each player has had a chance to achieve 1000 yards equal to the number of seasons that have happened since they were drafted there have been 356 possible 1000 yard season. Realistically not every player has a chance at 1000 yards because they can't all start. So if we assume there are 32 possible 1000 yard seasons each year, one for each team, there were 160 possible chances. Of all these chances a running back drafted between 2013 and 2017 has recorded a 1000 yard season 19 times. 13 unique players achieved this feat. Additionally there were 16 Pro-Bowl appearances by 12 of those players over this time. 

There is a pretty consistent trend of the percentage of 1000 yard seasons and 160 carry seasons achieved compared to possible chances. Players grouped by the year they were drafted hold the percentages in a narrow band (See Figure 2). For 1000 yards seasons it goes from 4-10% and gets lower the long ago that the draft took place. This makes sense considering those players drafted in 2013 have had much longer to get cut, hurt, or retire than those drafted last year. For 160 carry seasons the data sits between 12-17%. It spikes in the middle and is low in 2013 and 2017. Again this makes sense as players from 2017 have most likely not established themselves yet to earn all those carries nd players from 2013 have been cut, hurt, or retired.

Figure 2: The percentage of times a running back achieved a milestone in all the possible chances.

In both 2013 and 2014 no running backs were taken in the first round. Between 2015 and 2017 five running backs were taken in the first round. They were Leonard Fournette, Christian McCaffrey, Ezekiel Elliott, Todd Gurley, and Melvin Gordon. Of these five men only McCaffrey has not yet recorded a 1000 yard rushing season.  He is also the only player to not get at least 160 rushing attempts each season. In his only season McCaffrey rushed 117 times for 435 yards.

For the five drafts I reviewed 13 running backs were selected in the second round.  They have a much more spotty record than the first rounders. Le'Veon Bell leads the group with three Pro-Bowl seasons in five chances. Bell is widely regarded as one of the most talented running backs in the NFL. There are also two very notable busts in Montee Ball and Bishop Sankey.  Neither player ever recorded 160 or more carries in a season and both topped out around 550 rushing yards gained in a season. Another interesting second rounder is Christine Michael, who was drafted by the Seahawks in 2013. At the time I was confused by the pick because Michael had a limited playing history in college. It seemed to be a real reach pick. Although Michael never had a good season in the NFL, he never rushed 160 times or gained over 600 yards rushing, he has managed to stick around. He played in four seasons and is still on the Colts roster. Somehow Michael's time in the NFL just doesn't want to end.

If for each round you sum up all the times that a player drafted reached 1000 yards rushing, carried the ball at least 160 times, or made a Pro-Bowl, it becomes obvious that players drafted in earlier rounds are more likely to reach these milestones. The first and second rounds are the highest totals for all three metrics (see Figure 3). The second round looks better by count, but that is because more players were drafted, 47 compared to 10, so they had more opportunities than first rounders. To try and account for this looked at the percentage of times a player reached these milestones compared to the available opportunities.

Figure 3: Running backs selected in the first round achieved a milestone at a much higher rate than those drafted in other rounds.

For 1000 yard rushers the first rounders reached the yardage 50% of the available time. For second rounders is was only 13%. For rounds three and below it topped out at 5%. Basically if a running back is drafted in the first round they are much more likely to rush for a 1000 yard season than someone drafted in the second round and extremely more likely than someone in the third through seventh rounds.

Another metric to consider if someone is a productive NFL running back is the number of carries they get during a season. 160 carries means they averaged 10 per game. Looking at this metric by round shows a similar picture. Rushers drafted in the first round reached 160 attempts 90% of the possible opportunities. Second rounders only achieved this 38% of the time, while later round players maxed out at 12%.

For Pro-Bowl appearances the percentages are in line with the other metrics. First rounders were selected to the Pro-Bowl 40% of opportunities compared to at most 9% for the other rounds. Le'Veon Bell and Devonte Freeman made up 5 of the 12 Pro-Bowl selection for later round players.

Admittedly the percentages for first rounders should be way higher because the number of players is much smaller, so one great player can have a larger impact. For example there were 46 running backs taken in the sixth and seventh rounds, and only Latavius Murray has made a Pro-Bowl or rushed for 1000 yards. Also players drafted in those rounds are expected to bust more frequently because teams don't evaluate them as worthy of a higher pick. The teams drafting them don't expect much by taking them so low. It can also be argued that if first round players truly did bust at a higher than normal rate we should see the percentages drop and be much closer to the other round, which we don’t see. Instead we see the opposite. Players taken in the first two rounds have much higher percentages of successful seasons as measured by 1000 yards gained rushing, 160 rushing attempts, and Pro-Bowl selections.

Looking at all these stats doesn't disprove the conventional wisdom that NFL teams shouldn't draft running backs in the first round unless they are a generational talent, but it does make me question it more. Of the ten players taken in the first round only one hasn't reached the 1000 mark in a season yet, and he has only played one season. It is possible that all ten first round backs were exceptional generational talents, but it seems unlikely ten of these players would have shown up in five years. Those taken in the second round of the NFL are also generally very productive. So if a team is confident that a player is capable of making it in the NFL they should spend the pick. They have a good track record of evaluating college rushers and drafting accordingly.

Sources: Pro Football Reference