Choose a position Running Backs Quarterbacks Wide Receivers Tight Ends Kickers Defense and Special Teams Vernon Gholston joins a defense that was rebuilt in the offseason through the draft and a wide-open wallet in free agency. Al Pereira/Getty Images Football Preview   Position Rankings Jay Clemons: Top 200 Overall Players Greg Ambrosius: Top 75 Running Backs Greg Ambrosius: Top 30 Tight Ends Greg Ambrosius: Top 60 Quarterbacks Greg Ambrosius: Top 25 Kickers Greg Ambrosius: Top 25 Defenses Greg Ambrosius: Top 75 Wide Receivers Analysis Will Carroll: Quarterback injury report Gary Gramling: Most generous defenses Position battle: The 49ers QB derby Tom Carpenter: Potential breakout stars Will Carroll: Preseason injury prognoses From RotoExperts.com Scott Engel: 75 tips to success Matthew Greber: Top fantasy sleepers Paul Bourdett: Top fantasy busts Play Fantasy Football Sign up for SI's FREE fantasy football

On the Rise

Jets: New acquisitions Vernon Gholston and Kris Jenkins will add value to a defense that already includes fantasy stars Kerry Rhodes and Darrelle Revis.

Seahawks: This underappreciated group is led by Lofa Tatupu, one of the game's most active defenders.

Packers: With the offense in transition, Green Bay's outstanding defense and special teams will be called upon to do even more.

On the Decline

Ravens: This team has been defined by its elite defense for years, but this aging unit could plummet abruptly.

Steelers: They will still be among the best at keeping opponents off the board, but they won't score many fantasy points.

Giants: With Michael Strahan's retirement, they no longer have the best three-end rotation in the league.

Sleepers

Cardinals: Cornerbacks Antrel Rolle and Roderick Hood combined for five TDs last year, and Steve Breaston emerged as a top punt returner.

Colts: The return of pass-rush demon Dwight Freeney from foot surgery will kick-start a defense that ranked 26th in the NFL in sacks last year.

Raiders: The addition of All-Pro CB DeAngelo Hall gives Oakland's already strong secondary some added fantasy cachet.

Greg Ambrosius' Defense/ST Rankings

1. San Diego Chargers: The Chargers ranked fifth in points allowed per game last year, allowing just 17.8, but they added even more fantasy punch with 5 defensive TDs, 2 special teams TDs, 55 forced turnovers and 42 sacks.
2. Minnesota Vikings: The addition of DE Jared Allen makes this defense as good as any other in the NFL.
3. New England Patriots: Yes, it lost CB Asante Samuel to free agency, but LBs Tedy Bruschi, Mike Vrabel and Adalius Thomas lead a solid linebacking corp. More turnovers will come this year, so grab this D now.
4. Dallas Cowboys: The addition of Pacman Jones has this defense rising in off-season mock drafts. There's no guarantee that Jones will be eligible for the full season, but even without him the Cowboys forced 45 turnovers last year, scored three defensive TDs and had 46 sacks.
5. Green Bay Packers: The Packers have quickly become one of the most improved defenses under coach Mike McCarthy as last year it forced 41 turnovers, scored four defensive TDs and added 36 sacks.

-- Compiled by SI Staff

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