This offseason four prominent defensive coordinators on top defensive teams (Steve Spagnuolo - Giants, Jim Johnson - Eagles, Rex Ryan - Ravens and Jim Schwartz - Titans) have left - three for head coaching gigs and Johnson due to illness. Should we expect a major dropoff in defensive production for those squads?

In the Giants' case, I don't because the personnel should be better, and also because their coach, Tom Coughlin, comes from the Bill Parcells/Bill Belichick lineage, and their new defensive coordinator (and last year's linebackers coach) Bill Sheridan isn't going to change much about the scheme. But mostly, the return of Osi Umenyiora, the maturation of a young and talented secondary and the improvement and added depth on the interior of the line should more than make up for Spagnuolo's departure.

In the Ravens' case, I expect a moderate dropoff because Ray Lewis is a year older, they had some significant personnel losses (Bart Scott, Chris McAlister, Corey Ivy, Jim Leonhard) and they're bringing in Greg Mattison, a college defensive coordinator and not someone from within the same successful system. Not that Terrell Suggs, Lewis, Haloti Ngata and Ed Reed don't still constitute a formidable nucleus.

In the Eagles' case, I don't expect a big drop-off as defensive coordinator Sean McDermott was the Eagles secondary coach under Johnson, and I seriously doubt they'll change much if anything about the scheme. I'd expect Johnson's loss to be felt a year or two down the road as more players who don't already have experience in that system come onto the roster. The loss of Brian Dawkins could be an issue - especially with Johnson gone - but Dawkins was past his prime last year, and the team's secondary with Asante Samuel, Sheldon Brown, Ellis Hobbs, Quintin Mikell and Quintin Demps should still be quite good. (Incidentally, I would bet a substantial amount of money that no football team at any level (high school, college or Pro) had two Quintin's (spelled as such) as its starting safeties prior to the Eagles.

In the Titans case, not only did they lose Schwartz, but they lost their best defensive player in Albert Haynesworth. That said, Jeff Fisher has always been an excellent defensive-minded coach, and the team brought in Jovan Haye from Tampa to bolster the line. And second-year man Jason Jones had 3.5 sacks against the Steelers late last year when Haynesworth was out. Tennessee's secondary is still very good, with Pro Bowlers Cortland Finnegan and Chris Hope returning. Overall, I expect a moderate dropoff, but like the Ravens this is still a top-10 defense.