NFL's best pass-coverage teams

Richard Sherman talks a mean game, but where does Seattle rank in coverage grades? Matthew Emmons/USA TODAY Sports

When you look at the box scores for pass-coverage numbers, you can draw many conclusions. Unfortunately, those conclusions can often be wrong, since looking only at yards and touchdowns allowed can paint a far different picture than what's actually going on.

Our grading? It doesn't treat all yards as the same (think garbage-time, prevent defenses designed to slow the offense from getting into the end zone), and it accounts for teams spending more time in coverage.

The system also considers the fact that sometimes a defensive back can get beat and, whether it's an overthrow or a dropped pass, get off blame-free; had the pass been on target, the result would have been very different, but no thanks to the DB.

With that in mind, which NFL defenses are leading our coverage grades through five weeks?

Top five pass-coverage teams

1. Kansas City Chiefs: +27.9
Does this surprise anyone? By generating early leads, the Chiefs have been forced into a heavy dose of their dime defense (42.9 percent, with the league average at 4.9 percent), and they've showed impressive strength in terms of DB depth. The only downside has been the play of Dunta Robinson (a -5.9 grade), but the emergence of rookie Marcus Cooper (+3.4) has been the kind of pleasant surprise that helps mitigate the play of the veteran. Still, the stars of the show have been CB Sean Smith, thriving in new surroundings that have seen him in press coverage on 76.1 percent of snaps, and Eric Berry, our fourth-ranked safety on the season, who is really delivering on his talent.