Cover Me
Cornerback is one of the most impactful positions on a football field. A great one can eliminate the opponent's best receiving weapon and a bad one is a liability that can throw the entire defense into chaos.
A couple of weeks ago, due more to lack of any college football wide receiver data to crunch with the NCAA season still getting off the ground, I started poking around at NFL cornerback numbers. I'm no aware of any regular commentary floating out in cyberspace that focuses on this unsung position where the goal is to be so good they never call your name.
I started looking at three metrics to try to give context to the statistics:
- Attack Ratio: Total Targets/Total Snaps - The lower the better.
- Bleed Ratio: Total Yards Against/Total Snaps - The lower the better.
- Burn Ratio: (Total Interceptions/Total Snaps) minus (Total Touchdowns/Total Snaps) - The higher the better.
Each metric is stated as a Z-score (# of standard deviations from the mean) which is then averaged for a final score. The player data is aggregated on a team basis so we can see how the individual performances impact the team as a whole.
After an initial piece laying out the methodology and showing figures for the first week of 2020, we now have enough data through four games to do a deeper dive.
Let's look at player performance and then, teams.
(Note: The cutoff for qualifying was 147 snaps.)
Player Performance
Attack Ratio - Who's Hot?
- The above shows the top performers in terms of Attack Ratio with Z scores of 1.00 or better.
- Attack Ratio tries to reflect target frequency not just on passes, but on all snaps to account for how the opposing coaching staff might increase or decrease targets based on cornerback personnel.
- Marshon Lattimore is a man no one wants to tangle with as he is attacked about 5.3% of his snaps (Z score of 1.72 standard deviations from average).
- Every player with a top Attack Z has a Bleed Z above 0.00 meaning their Yards/Snap allowed are better than average except for Ronald Darby and Pierre Desir who have not been thrown on as much as you would think giving they are giving up yards at a worse than average clip. If offensive coordinators are paying attention, they will likely hit these two up aggressively in Week 5.
Attack Ratio - Who's Not?
- The above shows the cornerbacks through Week 4 whose Attack Ratio is represented by a Z score of -1.00 or worse.
- Not sure what is up with Shaquill Griffin, but he is a marked man as offenses have a target on his back. Not just is his Attack Z the most brutal (with him being targeted 16.5% of the time he's on the field) but his Bleed Z is horrific as well (I guess that's why his Attack is so high). He's going to have to shut someone down or the heat will just continue to get worse.
- Marlon Humphrey is on the list but it's pretty much a function of the opposing QBs have to throw SOMEWHERE vs. a solid Baltimore secondary. Notice that, despite him getting Attacked so frequently his Bleed Z is positive (meaning his Yards/Snap is better than average) so other teams are not getting their money's worth when they target MH.
- Jimmy Smith is getting the benefit of the shelling his teammate Humphrey (above) is enduring. His Bleed Z is the bes through Week 4.
- Funny thing for Kyle Fuller is, despite his elite Bleed Z, teams are throwing at him more than they would the average corner which, in this case, is far more than they should.
Bleed Ratio - Who's Not?
- No surprise here. Griffin is suffering from no slight case of overbombing. Will have to watch the All-22 to see what is going on here.
- Top CB in the last draft class Jeffrey Okudah is certainly getting his on the job training but after looking at him at OSU, I'm not giving up on him. This will help accelerate his rise in the league. You have to get the reps in to improve.
- The good news is that this list is relatively short and so most corners are in the middle somewhere.
Burn Ratio - Who's Hot?
- L'Jarius Sneed - "We must protect this house!" With no touchdowns allowed and 2 picks over 159 snaps, he's top gun in terms of Burn Z.
- You love to see the bend but don't break attitude with young players like Okudah and Jimmy Moreland who have had challenges in terms of Attack and Bleed but are keeping the dudes out of the end zone and each collecting a pick over 167 and 170 snaps respectively.
Burn Ratio - Who's Not?
- It's called Burn Ratio for a reason and Jason McCourty has been a human torch giving up 3 TDs with 0 picks over 151 snaps. He has respect because of a near 1.00 Z for Attack and positive Bleed so he might fly under the radar.
Team Performance
Here are charts for each Division comparing the aggregate Cornerback Attack, Bleed and Burn ratios to the QB Rating Z score for each team's Week 5 opponent (in parentheses underneath).
- NYJ corners have not been too bad per our metrics and they face a ARI passing attack that is below average (in terms of QB Rating).
- BUF's corners are talented but not really having a stellar season thus far and they face an above average TEN passing game (if the game gets played, that is).
- Although IND's passing game rates about average, they should be able to pepper the CLE CBs who have a pretty rough Attack Z (near 1.00).
- TEN CBs have been heavily targeted and will give up yards (far below average Attack and Bleed Z's) and here comes that BUF passing game. Not lookin good for the Titans.
- DEN has given up its share of TDs so it will be interesting to see how they fare against NWE.
- DAL and PHI are in luck because their opposition's QB Rating Z is far worse then their respective CB ratios.
- If you have Russell Wilson in Fantasy, start him this week. CHI and TAM were fairly equally matched up which reflected in their Thursday night game that came down to the wire.
- Not much here although TAM took on CHI this Thursday so it will be interesting to see how many of CHI's game high 42 pass attempts were targeting TAM CBs.
- ARI has above average ratios (but not stellar) but they fact NYJ which is more than 1.5 standard deviations worse than average. Perhaps Flacco (subbing for the injured Darnold) can find some of his old magic.
- Seems like SEA CB may have a "bend but don't break" CB philosophy - giving up yards between the 20s but stiffening in the red zone.
Feel free to leave comments about if this seems to have any merit or if you think it totally sucks.
Thanks and we'll follow up with updates for Week 5.
