Using Combine Stats to Predict RB Success: Part 1

For years, fans and analysts have argued the validity of the NFL Draft Combine. How much does it really predict? Which drills matter the most? While these answers may vary, one thing certainly agreed upon by most; this is not an exact science.
 With that being said, I will attempt to narrow things down and give a bit more clarity to these drills and how they can help predict success at the next level. Maybe more importantly for you dynasty players, how to find the players that will give you those top 20 seasons.

I will do so by taking all the numbers collected at the combine from 2006-Present, input them into a series of formulas, and extract them in a way that will help narrow down the risky players vs. the less risky players.

Formulas used:

  • Speed Score (weight adjusted)
  • Agility Score
  • Twitch
  • 3-cone Drill

To be clear, you will notice these lists aren’t broken down into draftable or not draftable lists. Simply put, they break down the players that are more risky than others. (NOTE: There were many 2017 players that didn’t participate in all the combine drills, some didn’t participate at all, so I used pro day stats instead.)

Well then, let’s get started, shall we!!

High Risk

First and foremost, we need to extract all the high-risk players first. These are the players that are more likely to not deliver you a top 20 season at the RB position, let alone multiple seasons of it. I will do so by first removing all the players with a Speed Score of sub 100. While some of these players may be “fast” when it comes to Combine speed, factoring in their weight is the true test. (NOTE: there are way too many players in this category, 126, so I trimmed the list down a bit.)

Here we see a large list of names that fall under the “High Risk” label. There were a total of 109 players (2017 eligible players excluded) with only a total of 16 players ever putting together a top 20 RB season. These players have a success rate of 14.7%, which is no good. If you expand that to players that have seen success and put together multiple top 20 seasons, the success rate is a staggering 8.3%. There are some notable players that went undrafted (Arian Foster) as well as a number of players with the one and done type seasons. There will always be those exceptions to the rule, of course, but needless to say, you may want to avoid these types of players. For the 2017 draft class, there are some notable, high ranking players on this list such as Alvin Kamara, Samaje Perine, and Jamaal Williams.

Moderate Risk

Now we need to move on to the moderately risky players. This group is made up of players that were able to score a Speed Score >100, but their agility isn’t as high. We will group these guys based on having an Agility score higher than 11.50.

This group and the ones to follow will have far fewer players in the pool. This group has a total of 26 players (2017 players excluded) with only five players seeing a top 20 RB season; that is a 19.2% hit rate. Four of the five players were able to achieve multiple top 20 seasons seeing a 15.4% chance that these players produce multiple top 20 seasons. One big, noticeable name among the 2017 RBs is Dalvin Cook who is rated very highly on most people’s boards. I wouldn’t avoid these players completely, but be sure to weigh your options closely and pay attention to where/when they get drafted. (NOTE: Elijah Hood is also part of this group.)

Low Risk 2

Now we start moving into the categories that are less risky and more rewarding for fantasy owners. These players also scored over 100 on the Speed Score, but their agility scores are less than or equal to 11.50. These are players that can better combine speed and agility.

Right off the bat, you can see the big named players on this list including players like Adrian Peterson, Maurice Jones-Drew, Chris Johnson, DeMarco Murray, among others. This list has a total of 48 players (2017 players excluded) with 14 players having a top 20 season; a 29.2% hit rate. This group also sees eight players with multiple top 20 seasons; a 16.7% hit rate. While this hit rate isn’t much higher than the Moderate Risk group, there are a few major differences.

First, the Moderate Risk group has one player with six top 20 seasons and the next closest player has three. With the Low Risk 2 group, you see Peterson with eight, MJD with seven, Chris Johnson with six, and DeMarco Murray with four which means this group has a chance at seeing more long term success than the Moderate Risk group.
 Second, there are six ultra-talented players with only one top 20 season, and all of them were drafted no later than 2013. If these players continue on a similar track, we could see the hit rate of multiple top 20 seasons jump to 29%!

We also have three players from the 2017 class on this list, a few of which are ranked highly by many in terms of talent. This is a group that dynasty players shouldn’t shy away from and actually should be looking to acquire.

Low Risk 1

This group is the last of the bunch and the one with the highest probability of success. Not only does this group combine the Speed Score >100 and Agility Score <11.50, but also adds in players with a Twitch score <1.25 AND a 3-cone <6.85. This list is very short, as can be expected, but will see a much bigger success rate.

This group has only 19 total players that qualify (2017 players excluded), but as you can see, there is a high hit rate. Of the 19 players, nine have seen a top 20 RB season which is a hit rate of 47.4%! Looking at how many players have hit multiple top 20 RB seasons, the hit rate is 36.8% (7 of 19). This group has seen some huge successes such as Matt Forte, Jamaal Charles, Ray Rice, and DeAngelo Williams along with some young players that are already putting together nice careers (Le’Veon Bell and David Johnson).

We can also see there are only TWO players in the 2017 class that fall into the Low Risk 1 category, Christian McCaffrey, and TJ Logan.

NOTE: Both Leonard Fournette and Marlon Mack had a speed score of over 100 but overall were incomplete due to not participating in all the drills.

Summary

To reiterate, this is not a list of do’s and don’ts when it comes to whom to draft. What this is, is a good way to help weigh the risks from player to player and help dynasty players decide on whom to draft. As you can see, when you continue to filter out players, the higher chance of success players will see. Tomorrow, in Part 2, we’ll see how this should be applied to draft ADP.


Originally published at dynastyfootballfactory.com on May 1, 2017.