What Trevon Diggs, Jalen Ramsey, Derwin James Jr., Tyrann Mathieu do at an elite level

The NFL’s most complete cornerback. The best blitzing safety. The players with the most range to find the ball in the air. Even the best ball hawks. It’s time for the sixth edition of the Shutdown Index, in which I pick the NFL’s best defensive backs in 25 different categories. Of course Trevon Diggs — who leads the NFL with 10 interceptions — makes an appearance, but you’ll also find Tyrann Mathieu, Jalen Ramsey and Justin Simmons. Darius Slay, who has had a resurgent 2021 season, is on the list, along with a few…