Analyzing the D: Rebuilding is the theme

Four years ago, the Jets had a ball on defense, blitzing and confusing opponents on their way to the No. 1 ranking in the NFL. These days, it's all about a different kind of ball -- the wrecking ball.

Since the end of the season, they cut three starters and lost three in free agency. One starter returned Tuesday, with the re-signing of OLB Calvin Pace. In the coming days, they may trade shutdown corner Darrelle Revis to the Bucs, leaving a barely recognizable unit.

Rex Ryan is a terrific defensive mind, but this lineup purge will test him in ways he never could've imagined.

The goal is to get younger and faster, especially at linebacker. The Jets stayed with the Pace-Bart Scott-Bryan Thomas-David Harris quartet one year too long, and it cost them dearly. Nose tackle Sione Po'uha, also released after the season, got old in a hurry, hurting the once-formidable run defense.

The Jets will build around Harris, cornerback Antonio Cromartie and linemen Muhammad Wilkerson and Quinton Coples, counting on young players and relatively inexpensive free-agent additions to step into front-line roles. Linebacker Demario Davis and nose tackle Kenrick Ellis are projected starters, with linebacker Antwan Barnes and safety Dawan Landry -- cost-effective pick ups in free agency -- also slated for starting roles.

But that isn't enough. They need at least two immediate starters to come from the draft, and one of them has to be a pass-rushing outside linebacker. The sack production has declined steadily under Ryan, who never has had a blue-chip pass rusher in his stable. They could find one with the ninth overall pick.

Dion Jordan (Oregon) would be ideal, but he probably won't be available. Barkevious Mingo (LSU) offers tantalizing speed on the edge, but he's undersized and his college production doesn't match his talent. In another words, he's a risk. Jarvis Jones (Georgia) is a big-time playmaker, but there are medical and scheme-fit concerns.

There could be a couple of attractive linemen still on the board, but it would be tough to justify a first-round linemen for the third straight year. They're also desperate for a safety, but they should be able to find a potential Day 1 starter in the second or third round.

You could see a philosophical shift from Ryan, who built the previous version of the defense from the back end -- an emphasis on cornerback play. But with Revis seemingly on his way out, and with so many young players on the line, they will put the focus on the big fellas. It makes it imperative they find a pass rusher in the draft.

SPECIAL TEAMS: The unit was a mess last season, but all the key people are back (kicker, punter and returners) and they should be able to find more core special teamers in the mid to late rounds.