Meet the Metric: Shadow Rate

by Neil Dutton · Analytics & Advanced Metrics

Most of the major stats and metrics on offer at PlayerProfiler focus on the offensive side of the ball. These are the players most likely to score fantasy points, after all. So, it stands to reason that they get most of the attention. But we do not completely neglect defensive players. We have a whole host of numbers and metrics on those guys as well. One of the newer metrics people may have spotted amongst defensive backs’ profiles is “Shadow Rate.” Sounds dark and mysterious, doesn’t it? So, what is it? Let’s meet the metric.

What is it?

Our definition of Shadow Rate is “the percentage of cover snaps a defensive back is assigned to a particular receiver on the play as opposed to the side of the formation.” We want to know how often a cornerback’s sole focus is one man and one man only. The beauty of this metric is it shows how often a team asks one of their defensive backs to make a particular pass-catcher their No. 1 priority, going wherever they go to shut them down. Becoming their “shadow,” as it were.

It would be fascinating to go back through time to see the Shadow Rates of legitimate shut-down corners like Deion Sanders and Darrelle Revis. I imagine it would be high. But this is a potential pet project for one of our legions of game analysts. This a team that YOU could join by the way.

The League of Shadows

The leader of this League of Shadows in 2021 was J.C. Jackson, then of the New England Patriots. His Shadow Rate was 59.6.

J.C. Jackson Opportunity Stats 2021

Looking at all cornerbacks who played at least 650 snaps last season (there were 49), the top five is rounded out with Kristian Fulton (57.1), James Bradberry (55.8), Shaquill Griffin (55.6), and Trevon Diggs (55). Bradberry’s inclusion in the list makes for interesting reading considering his new home for 2022. Bradberry signed a one-year deal with the Eagles after his release from the Giants. He joins Darius Slay in the defensive backfield, giving Eagles defensive coordinator Jonathan Gannon two players with legitimate shadow experience. Slay was No. 11 in Shadow Rate last season at 52.7.

Being tasked with going everywhere their man would go does not mean that quarterbacks were afraid to target these players, of course. Nor does it mean that they were able to erase all receivers from the stat sheet. Bradberry, for instance, was No. 13 among qualifiers allowing 3.1 receptions and 39.9 yards per game. Diggs was the ultimate boom or bust player of the leading shadows. He led the NFL with 12 interceptions while only allowing 2.6 receptions per game (No. 29). But he allowed 50.4 yards per outing (No. 4) with the average catch going for 19 yards (No. 1). Sometimes shadows turn out to be holograms.

Surprise Stud

While researching this piece, it came to light just how good a season Jaguars cornerback Griffin had.

Shaquill Griffin Advanced Stats & Metrics Profile

Griffin signed with the team as a free agent, and they sent him out as a shadow corner at a 55.6 rate. He allowed just 2.4 receptions (No. 34), 26.5 receiving yards (No. 40) per game, and gave up a mere 11 yards per reception (No. 38). His ball skills could have been better, as he broke up just seven passes (No. 45), and failed to log a single interception. But among those most often tasked with shadowing a particular receiver, Griffin’s numbers speak for themselves.

Go well, everyone.