When it comes to fantasy team defenses, it doesn't take a sixth sense to comprehend the deadly dominance of 3-4 schemes.
With 3-4 units holding down the top six spots in PFW's team-defense rankings, the numbers don't lie.
It's also worth noting the defensive firepower in the NFC North, with three of the division's four teams cracking the top 10.
1. Pittsburgh Steelers
Key stat: The Steelers limited opponents to a league-low 14.5 points per game last season, holding seven teams to 10 points or fewer (all victories).
The skinny: With venerable Hall of Famer Dick LeBeau continuing to coordinate a defense overflowing with experienced Pro Bowl-caliber performers at every level such as OLB James Harrison and SS Troy Polamalu, it's easy to see why the Steelers get top billing for yet another season.
2. Green Bay Packers
Key stat: Dom Capers' often-dominating unit held six 2010 opponents to seven points or less on the road to a Super Bowl title, including a shutout on the road against the Jets in Week Eight.
The skinny: You can't go wrong with a secondary that's second to none — Green Bay led the league in opponents' passer rating (67.2) and finished second in interceptions (24). The "D" features outstanding young defenders such as CB Tramon Williams, NT B.J. Raji and the relentless Clay Matthews, who spearheads a very deep, talented LB corps.
3. Baltimore Ravens
Key stat: Despite allowing more yards per game last season than in any other campaign since 2002 (318.9), the Ravens ranked third in points allowed (16.9 per game) for the third consecutive season.
The skinny: Forget its uncharacteristic shortcomings last season, particularly against the pass. With MLB Ray Lewis, DT Haloti Ngata, OLB Terrell Suggs and FS Ed Reed among the best at their positions, this defense still packs a mighty fantasy punch.
4. New York Jets
Key stat: The Jets allowed 10 points or fewer points in five games last season and finished second in the league with 18 fumble recoveries.
The skinny: While not as dominating as it was two seasons ago, the Jets' "D" will always be a fantasy force as long as head coach Rex Ryan is running the show.
5. San Diego Chargers
Key stat: The Chargers allowed a league-low 271.6 yards per game and ranked fourth against the run after finishing 20th in that category the previous season.
The skinny: Greg Manusky replaces the well-regarded Ron Rivera as the coordinator, but it's doubtful there will be much of a drop-off with the team adding free-agent SS Bob Sanders and four defenders in the first three rounds of the draft.
6. New England Patriots
Key stat: The Pats led the league in interceptions (25) and turnover margin (plus-28).
The skinny: New England's bend-but-don't break defense could be the most opportunistic unit in the league. In addition, its special teams excelled on returns and blocking kicks last season.
7. Chicago Bears
Key stat: The Bears ranked fourth in points allowed in 2010 after tying for 21st the previous season and also improved from 23rd to second against the run.
The skinny: You can't go wrong with DE Julius Peppers and LBs Brian Urlacher and Lance Briggs among the best at their positions. Plus, Devin Hester leads one of the league's best special-teams units.
8. New Orleans Saints
Key stat: The Saints improved from 26th to fourth against the pass but managed only nine interceptions after picking off 26 passes the previous season.
The skinny: Despite giving up 41 points in a nightmarish playoff loss to Seattle, Gregg Williams' aggressive unit still warrants top-10 status after adding new blood via free agency (DT Shaun Rogers) and the draft (first-round DE Cameron Jordan).
9. New York Giants
Key stat: The Giants led the league in takeaways last season with 39 and ranked fourth in sack percentage.
The skinny: The defense comes up a little short at linebacker, but there are only a few groups as talented as coordinator Perry Fewell's stop unit.
10. Detroit Lions
Key stat: The Lions ranked fifth in sack percentage and limited the world-champion Packers to a mere three points in a late-season victory.
The skinny: With 2010 first-round DT Ndamukong Suh quickly becoming one of the league's top defenders, the sky's the limit for this up-and-coming unit.