Should Teams Spend More on Cornerbacks?

Roster construction is a very interesting thing in the NFL. In many ways it’s a chess game where you have to adapt as the league changes, changes that are generally dictated by the offense. As passing games explode teams have to move away from the traditional construction focused on linebackers and run stuffers and generally move more to help in the secondary. I wanted to look at how teams are investing in the corner versus wide receiver game these days and seeing if it is something that can be tweaked.

The concept of receiver vs corner has always fascinated me. Really it goes back for me to the peak days of Darrelle Revis with the Jets in 2009 and 2010 when we came across debates of sorts as to who was better- Revis being thrown on often and breaking passes up or Nnamdi Asomugha who just never got targeted. My take on it then was that there was far more value in having a player like Revis because a breakup of a play is a complete shutdown. It’s a non-gain or a limited gain for the offense. Lack of targets just causes the ball to cycle from WR1 to WR2 and even if Asomugha matched up against the top target each play (he did not) the offense would still be efficient.

This was what wound up killing the Jets in the championship game that year against the Colts in which Revis pretty much made Reggie Wayne irrelevant, but around the end of the first half Peyton Manning realized that playing opposite Revis was Lito Sheppard and Dwight Lowery (at least I think those were the two) and Austin Collie and Pierre Garcon went off for nearly 300 yards. The Jets would come back the next year with a team that featured a high priced Revis, a high drafted and eventually highly paid Antonio Cromartie, and a 1st round draft pick in Kyle Wilson. Whether on purpose or by accident the Jets stumbled into a group that had the potential to essentially have two number 1 corners of varying ability and at worse a number 2. It never worked out that way as Wilson busted and Revis and Cromartie only really played two seasons together, but I thought the concept was good. Im sure there are other examples but as a Jets fan this was the group that always stood out to me in the more modern NFL era.

So I wanted to see if that same concept might hold today. I looked at PFF’s stats for WR’s since 2015 and ranked every WR by their position on the team based on targets between 1 and 5. Here is the expected performance.

WRTgtsRecCatch RateYardsyds/tgtyds/recTds1stDInt

The numbers make sense in that the 1st receiver is the most dominant target over the course of a season but most of those numbers are generally a byproduct of opportunity. If you look at the yards per target column the dropoff from a 1 to a 2 is only about 2.6%. This is one of those reasons why so many consider the QB the driver of offensive performance and one reason why there is so much variance on a weekly basis from receivers as the big game potential exists if they find a favorable matchup/gameplan.  If you use a net yardage type formula which will bump the number 1 performance for 1st downs, touchdowns, etc…its about a 3.5% drop on an opportunity basis. A drop from a 1 to a 3 is about 8.5%, to a 4 is 11.5%, and to a 5 is 17.5%.

To that end I kind of wonder why (or if) more teams are not attempting to put supergroups together that do the best job possible of cycling off not just the top target on the field but trying to get the offense to be forced to spread out further and drop down to those 3rd, 4th and 5th players or to generally more ineffective routes for running backs and most tight ends.

Here is a look at how much the NFL spends for their cornerbacks, ranked 1 to 5 by salary. Since draft picks have a low salary relative to their expected contribution I converted the salary of any draft pick still on a rookie contract to the expected APY using the Fitzgerald-Spielberger valuations that Brad and I worked on in the Drafting Stage. The only exceptions were for those who had an option year in play as they were valued at the option value if it was picked up.

RankAverageQuartile 1Quartile 2Quartile 3

Here is the breakdown for wide receivers.

RankAverageQuartile 1Quartile 2Quartile 3

This isn’t meant to compare salaries (I’d say a quick takeaway is that teams find receivers about 18-20% more important to winning based on the numbers), but to give us an idea as to how teams construct their rosters.

In looking at the numbers teams more or less go with a matching strategy. 18 teams have at least one average paid number 1 corner while 16 have at least one number 1 receiver. 25 teams have at least one “high end” (an upper quartile 2) number 2 corner while 23 teams have at least one “high end” number 2 receiver. Here are some of the combinations that exist in terms of groupings of talent.

Avg 1 and High 289
Avg 1 and Avg 21111
At least 2 Avg 21513
At least 2 Avg 2 and Avg 387
At least 3 Avg 31512

There is a little disparity as you get to the teams with at least two average number two or three average number 3 receivers, but nothing too crazy.

But in general offenses dictate matchups and we mentioned above there is not that kind of a dropoff if you force a team to go to their number 2 or even number 3 target. However, when you look at corners there is more of a disparity. The top player on a yards per target basis on a team gave up around 6.4 yards. The second jumps to 7.8. The average third is around 8.5. While the coverage assignments are playing a role in these numbers and one would really need to dig deeper I would think the best way to slow down a passing game is not to go 1 for 1 but to stock up on higher end talent via the draft, trade, and free agency to potentially field a team that can force teams out of their typical patterns of wiping out the weakest link on a team.

Surprisingly the concept of the “cornerback supergroup” really doesn’t exist. Only three teams in the NFL currently have three players under contract who would rank as either an average CB1 and CB2 in the adjusted salary scale I used here. Those teams are the Dolphins, Lions, and Ravens. This is on par with the offense that has three teams with at least 3 receivers who are paid above the average WR1 or WR2 level. However as we drop down there are 7 teams on offense that have at least 4 receivers that rank above the average for a WR3. Defensively we have just 1 that goes four deep- the Patriots.

This just seems short sighted especially since we do see variance not just player to player but often season to season. One of the ways to minimize that risk is to treat the roster just as you would a stock portfolio (similar to my concept of picking multiple top QBs in the draft if you can). Players are always going to bust but the impact of the bust is deadly when there is no alternative option. We reduce that risk dramatically by also investing in another high potential player.

As a way to go a little deeper into this I decided to look to our friends at Pro Football Focus and look at their coverage grades they assigned to corners between 2015 and 2019 who played 300+ snaps and then grouped each of those players by salary and contract type. The lines are the average PFF grade of about 65 and salary around $4 million.

Basically, in every grouping of talent, you see a pretty strong distribution of above and below average seasons. To remove some of the clutter here are the numbers in table form. Please note I broke the free agents up into high and low dollar figures ($5.75M was the cutoff)

OutcomeUDFAExtensionDraftHigh $ UFA/SFALow $ UFA/SFA
Above Average3938944933
Below Average34161303853
Success Rate53.4%70.4%42.0%56.3%38.4%

Because I cut off the numbers at 300 snaps you can discount the UDFA numbers because these are the best of the best UDFAs that warrant playing time. For the other groups the list is much more inclusive especially for free agent signings.

There were two things that caught my eye. One is that teams surprisingly seem to make pretty good extension decisions. The second is that spending on bigger money free agents is resulting in more success stories than those who are wasting money on the lower salary tier. If we go back to our original tables which identified an average number 2 corner at costing around $6 million basically spending below that level in free agency is going to provide diminishing returns.

What if we looked at the draft by round?

Above Average4120147633
Below Average353120181169
Success Rate53.9%39.2%41.2%28.0%35.3%33.3%25.0%

Here again you need to focus on the top rounds because the further we go the more misleading the numbers because we have disqualified so many seasons by having a 300 snap limit. Its basically going with a first round player and then the 2nd and 3rd. The other rounds aren’t planning for a starter they are basically lucking into one similar to the UDFA route.

Our goal is to best ensure we wind up with at least two good corners in any given season. If you have failed to do well in the draft in the past the best route to  that is to sign two expensive players and draft a player high in the draft. If you happen to have landed a player you already know you are going to extend the best thing to do is to sign an expensive player and draft another where you are staggering the salaries.  A rough estimate of a 3 corner matrix using some IPA fueled math in a few configurations would be as follows

Scenario3 Above Avg.At least 2 Above Avg,3 Below Avg.
Extension/1st rnd Draft/Exp UFA21%65%6%
2 Exp UFAs/1st Rnd Draft17%58%9%
1st round/2 Cheap UFAs8%40%17%
3 Cheap UFAs6%33%23%

The first scenario if you do it properly has two rookie contracts running concurrently for a period of time. Basically it means after the rookies 2nd year you know he is an extension candidate so you go in sign a free agent for year 3 and draft a rookie. By the time the first rookie is actually up for a new contract you should know if the 2nd 1st rounder is also great or not. If hes great you are a team with two extension quality players and you can decide what to do with the 3rd.

The 2nd scenario is when you have flamed out in the draft. You sign guys to improve the team ASAP while developing a 1st. You can do this after 1 season of a rookie contract or most of it concurrently. Doing it concurrently is a bit more of a blind bet but can make you much better faster.

The other two scenarios which are more in line with most NFL rosters (remember most don’t even have 3 third tier corners) doesn’t give you the odds needed to really hit a home run in your coverage. Its why there is probably an argument that if you aren’t going to spend on the position outside of one blind pick you may be better off just punting on the position and calling it a loss. That lone 1st round pick isn’t going to cut it.

The possibilities are pretty much endless but the gist of it is the more players you try to fill up the room the better chance you have of pushing the offense off their typical norms by optimizing the chance to hold down those first two and hopefully 3 targets in an offense.

Given the way the league has gone its far more important to be able to provide strong coverage in the secondary on 1,000 snaps in a year than provide a pressure on 80 snaps a season. There is a cost benefit here in free agency since corners are discounted at 20% on receivers and even more on pass rushers. Teams can exploit that by doing a bit more “supergroup” planning rather than just piecing the secondary together the way they currently are which has way too much over-reliance on one player.