The Cover 2 is a zone defense that relies on two safeties covering the deep halves of the field. Two cornerbacks and three linebackers divide the field into fifths and play zone underneath, while four defensive linemen must get to the quarterback before he has time to expose the limited deep coverage.
There are four keys to the Cover 2 scheme: 1) both safeties must have the range to cover half the field; 2) the corners must hold up receivers at the line so they don't run free into the deep secondary; 3) the middle linebacker must get a deep drop to protect the middle of the field; and 4) the defensive linemen must get to the quarterback before receivers find holes in the zone.
Shawne Merriman plays with his hand on the ground in the Cover 2 defense.
Of course, San Diego won't run much pure Cover 2. That defense is best run by smaller, quicker defenses, and the Chargers' defense is anything but small.
San Diego's starting D-line has an average weight of 315.5 pounds, and the starting linebackers weigh an average of 253.5 pounds. The Colts, by comparison, don't have a D-lineman who weights more than 301 pounds or a linebacker who weighs more than 240 pounds.
Instead, most of San Diego's Cover 2 looks will be a variation of the scheme known as Cover 2- Man Under. This formation has the same principles as the Cover 2 -- safeties playing deep halves with a four-man front -- but the cornerbacks and linebackers play man coverage underneath.
When playing Cover 2- Man Under, San Diego deploys a front-four consisting of Jamal Williams and Igor Olshansky at tackle and Luis Castillo and Merriman at end. Wilhelm serves as the ‘Mike' linebacker with Shaun Phillips and Stephen Cooper flanking him.
This front-seven works because Merriman plays well with his hand on the ground and Phillips gets to rush the quarterback if the running back doesn't release out of the backfield.
The secondary is much better suited to run Cover 2 than it was last season, as Weddle has much better range than Marlon McCree. The unit is particularly apt in Man-Under variation, as Jammer and Antonio Cromartie excel in man coverage.
Don't expect an abundance of Cover 2 in 2008, but count on Ted Cottrell dialing it up from time to time. When he does, look for the Chargers to be extremely effective in implementing it.
Michael Lombardo is a member of the Pro Football Writers of America and a long-time contributor to the Scout.com network. His analysis has been published by the NFL Network, Fox Sports and MySpace Sports. He has followed the Chargers for more than 15 years and covered the team since 2003.