The more I watch sports, the more I am fascinated not with the superstars but with mediocre players.

Now, I want to acknowledge that I played organized football for just one year. I was the nine-year-old center and nose tackle for a church school association team. I was terrible at it -- and still would be today.

So, when I say “mediocre,” I don’t mean that these guys couldn’t pancake me and everyone in my immediate family with one hand. I simply mean that they are basically average players in their respective sports but still hang on in the league (hey, Tim Tebow).

“Sticking with it” is a skill in and of itself, and I take nothing from that. I just love to watch guys who seem a little closer to me on the spectrum of humanity instead of immortals walking amongst us in pads.

That’s the trick for finding a cornerback matchup to start wide receivers against in fantasy football, as well. When we look at the season as a whole, as we will today, I hope to identify defenders who give up plenty of value to our fantasy wideouts but still keep their jobs.

It’s much easier to smash the “submit lineup” button knowing you have a cake matchup for your receivers, and it's even better if we can find guys to keep coming back to.

Which cornerbacks should we look forward to starting our fantasy wide receivers against in 2021?

Process

There are a few ways to group the best cornerbacks to target for wide receiver fantasy success. The categories I’m evaluating them on are “slot” (the best cornerbacks covering interior pass routes), “speed” (against quicker receivers), “possession” (against stronger receivers), and “overall.”

To assemble my ratings for cornerbacks, I compiled general coverage data from Pro Football Focus for the 2018 to 2020 seasons. I combined that with two specific player tracking metrics from PlayerProfiler.com: Target Separation (the average distance of a defender from their assignment when the ball arrives) and Burn Rate (the percentage of targets where an assignment was 5 yards or more downfield from the defender).

I assigned a percentile rank to each stat, target rate (targets per coverage snap), catch rate allowed, yards per coverage snap, and yards after catch per reception (YACR).

For the “speed” category, I added in Target Separation and Burn Rate, which will show how much the receiver’s suddenness and raw velocity overwhelmed them.

When evaluating corners versus “possession” receivers, we prioritize their catch rate allowed and forced incompletion rate in addition to the overall metrics.

Then, weighting each percentile rank, I combined them to form a rating for each category.

Versus Speed Receivers

Cornerbacks who performed particularly poorly against speed receivers are below.

Chicago Bears 2020 second-rounder Jaylon Johnson is a fascinating case, posting a rating more than two times as forgiving against fast wideouts than possession ones. Despite this, Johnson was actually one of the stingiest coverage players overall last year, ranking 29th-lowest among the 96 projected starting cornerbacks in overall coverage rating. Johnson came into the league with a reputation as a stout press-man defender, a boon against strength-based receivers. NFL.com’s draft profile for him suggests he gets “jittery and impatient,” which leads “to lunging and reaching,” a tendency that gets him off-balance and “opens deep threats from speed” -- a fact we see borne out in the data.

The speedier receivers Johnson might face this year include Odell Beckham (Week 3), Breshad Perriman (Week 4), Henry Ruggs (Week 5), Marquise Brown (Week 10), and Tyler Lockett (Week 16).

Fellow sophomore secondary member Trevon Diggs of the Dallas Cowboys joins Johnson at the top of this list. Diggs might be generally more appealing as a cornerback matchup to start receivers against, as he came in 20th-best for receivers in our overall matchup rating as well. Diggs so far has an average Target Separation of 1.2 yards and a 2.5% Burn Rate (88th and 78th percentile marks, respectively). He allowed 0.43 PPR fantasy points per snap when facing receivers one-on-one, and his pre-draft profile also identified speed as a potential weakness.

This year, Diggs could end up having to stop Mike Williams (Week 2), DeVonta Smith (Weeks 3 and 18), Robby Anderson (Week 4), Tyreek Hill (Week 11), Ruggs (Week 12), and Terry McLaurin (Weeks 14 and 16).

Versus Possession Receivers

Cornerbacks who have performed particularly poorly against possession wideouts are below.

The New Orleans Saints’ secondary has gotten a worse rap than they deserve in recent years, mainly for high-visibility failings in big moments. Cornerback Patrick Robinson is largely one of the better defenders among projected starters this year, ranking 30th-worst as a matchup for receivers overall, but he has been significantly stouter against speed than strength. He wasn’t targeted a ton in man coverage (just 13% target per snaps) but gave up a 75% catch rate and 13.1 yards per reception in that phase. Robinson isn’t the best option to start a possession receiver against, allowing just 0.23 PPR points per snap, but he should be avoided at all costs if he’s set on a speed receiver.

Robinson is set to square off in 2021 with Allen Lazard (Week 1), Kenny Golladay (Week 4), Julio Jones (Week 10), Amari Cooper (Week 13), Corey Davis (Week 14), and DeVante Parker (Week 16).

Recent third-rounder Justin Layne is the second-worst cornerback against possession relative to speed but is in line to start for the Pittsburgh Steelers in 2021. Layne admittedly has a small sample size of snaps in his two years in the league so far, accumulating just 98 total, but those show some vulnerabilities so far. In man coverage, he has seen a target rate of 22%, allowing a 67% catch rate and 16.3 yards per reception on those opportunities. In two NFL years, he himself has forced no incompletions.

This year, Layne should have to take on Bryan Edwards (Week 2), one of Tee Higgins or Ja'Marr Chase (Weeks 3 and 12), Lazard (Week 4), D.K. Metcalf (Week 6), and Adam Thielen (Week 14).

Versus Slot Receivers

Cornerbacks who have performed particularly poorly against slot receivers are below.

Jacksonville Jaguars cornerback Shaquill Griffin has been a terror to outside receivers, with his overall rating in my system the 11th-worst for fantasy wideouts among projected starting cornerbacks. He has allowed just a 12% target rate, giving up a mediocre 63% catch rate when targeted. Receivers have only earned a paltry 12.9 yards per reception against Griffin, and he’s allowed very little separation. When forced into the slot, however, Griffin’s effectiveness nosedives. He has been targeted on 23% of his snaps there, giving up an 87% catch rate for 10.6 yards per reception -- nearly the same distance but from a position where short routes are way more common. Now as the Jags’ CB3, there’s a chance Griffin is forced to cover the slot more by happenstance.

The same effect has happened with Patrick Peterson, now of the Minnesota Vikings. When forced to shadow receivers into the slot, he sees a target rate and catch rate nearly 10% higher and actually gives up 2.4 more yards per reception from the slot. Hopefully for us his new team doesn't realize his interior shortcomings and use Bashaud Breeland or Cameron Dantzler there instead.

Versus Overall Receivers

Cornerbacks who have been particularly vulnerable to wide receivers overall are below.

The top five in this category are all 2020 rookies. Since rookie cornerbacks often struggle, we could see some of these players develop into better coverage corners in 2021, their second year. I’d specifically assume the Detroit Lions’ third overall selection, Jeff Okudah, will take a leap forward this year with some experience under his belt. Amik Robertson and Damon Arnette of the Las Vegas Raiders I expect in particular to continue allowing production, however, especially considering their poor pre-draft evaluations and the talent they face in their own division.

It’s never too early to begin looking for the edges in a fantasy football season. Whether you play season-long, DFS, dynasty, or something else entirely, the earlier you can paint a target on particular defenders’ backs, the better you can establish a benchmark to work from in season. That’s just one way we can improve our fantasy football process from mediocre to at least halfway decent.