Athletic testing and cornerback success in the NFL

About a month and a half ago, after one of the recording sessions for the AP Laboratory podcast, talk turned to the wonderful Force Player metric that Justis Mosqueda developed for evaluating pass rushers in the draft. As the conversation evolved to discussing a metric that could be used to identify cornerbacks, I took it upon myself to see if I could find any trends or connections that the NFL has had in recent history with cornerbacks coming out of the draft.

That set me off on a potential road to nowhere and resulted in a multiple-day project digging into every cornerback that was drafted or invited to the combine from the 2010 combine to the present — as well as a handful of others like AJ Bouye and Chris Harris Jr that weren’t drafted or invited to the combine. I ended up with 382 players from the past 10 years and their athletic testing data.

Before we go any further, I’ll address the elephant in the room.

Athletic testing doesn’t matter if the player has poor mental makeup or poor technique. A bad football player that can run fast is still a bad football player. However, with varying collegiate schemes, coaching staffs and overall development of players coming into the draft, it’s not easy to get a bead on where players can develop and which ones will fall by the wayside. The only real “level playing field” for each player that scouts can use is athletic testing.

Back on the data, I sorted out the contributors — players that started eight or more games a year on average through their career, started a full season for a team or played more than 60% of the snaps for a team in multiple seasons — and I looked for correlations. I created a weighted formula using the following factors for the following reasons:

• Length/size/arm length — Ability to cover any size of receiver
• 40 time — Ability to cover fast receivers on vertical routes
• Vertical jump/broad jump — Explosion to attack the ball at the catch point
• 3-cone time — Ability to transition in and out of breaks
• Bench press — Work ethic

Bench was a surprising metric that had a very strong correlation to success. While it’s not something that translates particularly well to the field, it does show a willingness to put in the “extra effort” and can help identify some work ethic traits.

Once I finished up the formula, I was able to run some calculations and found the early-round freak athletes I expected near the top: Patrick Peterson, Byron Jones, Jalen Ramsey, Denzel Ward and Devin McCourty to name a few. I also found my share of mid-to-late-round contributors like Buster Skrine, Coty Sensabaugh and Shaquill Griffin.

Meanwhile, the bottom of the list contained contributors that converted to safety — Tyrann Mathieu, Damontae Kazee and Lamarcus Joyner, to name a few — and players that succeeded very well inside a specific scheme, like Josh Norman and Malcolm Butler. Some outliers bucked trends, but the players largely fell into four tiers. Looking at the success rates of those tiers gave me the following percentages of obtaining a contributing player out of each tier:

Acquiring an upper-echelon athletic tester — regardless of tape, round, or specific scheme — resulted in a staggering success rate over the league average in this timespan. Teams were almost two and a half times more likely to draft a contributing player than they were over the next lowest tier.

Keep in mind that the NFL found a contributor a paltry 25.59% of the time within this data set. With a one-in-four chance overall at finding a player that earns their roster spot with on-the-field contributions, targeting the top tier of athletes resulted in a three-in-five chance at doing the same thing.

It’s not just at a “contributor” level that the differences are stark. Looking at each tier individually, we can see the likelihood that a player drafted will be a first-team Pro Bowler or a first-team All-Pro.

By merely targeting players in the upper athletic testing tier over the past decade, NFL teams have had a one-in-five chance at drafted a first-team Pro Bowl player and a one-in-10 chance at drafting a first-team All-Pro player. This doesn’t include repeat nominations — Patrick Peterson didn’t count for multiple entries — individuals who were nominated only counted once.

These numbers are supported when you look at the averages per player in each tier since 2010:

Cornerbacks in the top tier of athleticism start nearly twice as many games on average and have one and a half times as many interceptions and pass breakups as their counterparts in other tiers.

It’s not easy to get into this upper tier of athletic testing. Only 11.2% of the qualifying cornerbacks were able to qualify. It’s no wonder that all but one of the players in the data set were drafted in the last decade.

Rich Barnes-USA TODAY Sports

So what does this mean for the 2019 draft class? We don’t yet know who will be drafted from the group that participated in the NFL Scouting Combine this year to identify all of the players from this group of data, but looking at the combine numbers shows seven players that are identified as Tier 1 athletic testers in this draft class. Only 2017’s draft class contained more players that hit the mark with eight.

Two members of this year’s 25 days of Draftmas list are in that top tier: Sean Bunting and Corey Ballentine. Another couple players discussed often — Justin Layne and Rock Ya-Sin — are part of the second tier. Some of the hotter names for Chiefs fans reside in the third tier in Byron Murphy, Deandre Baker and Trayvon Mullen. Finally, tier four contains names like Saivion Smith and Hamp Cheevers.

These tiers aren’t measures of success for any of these players — again, technique and mental makeup are significantly more important. None of the seven players that have the top tier of athleticism are currently considered first-round picks, where the majority of the players picked become contributors. More so, only two of the players are even universally considered to be top-100 picks in this year’s draft.

This draft should give us a glimpse of if these trends are continuing. If the NFL gets production out of several day-three picks with top-tier athleticism, there might be a serious correlation that is worth considering here.

And if they don’t? Well, it’s a failed hypothesis for yours truly.

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