Power Rankings: How do you spell unbeaten? D-E-F-E-N-S-E

Updated Sept. 30

Take a look at the top three teams in the CBSSports.com Power Rankings. The New York Giants, Tennessee Titans and Buffalo Bills are all undefeated, the only three teams without a loss.

They also have something else in common, which is why they are where they are -- it's called defense.

As much as I hate to admit it, since I am a connoisseur of offense, defense is ruling the NFL early on.

As we raced to anoint the Dallas Cowboys as the team to beat, we lost vision of their so-so defense. Buried under their high-scoring, fun-to-watch offense is the Cowboys' 20th-ranked scoring defense, which is giving up 22.2 points per game.

The top three teams in the rankings are all in the top 10 in scoring defense. The Titans are tops in the league with an average of 11.3 points allowed, followed by the Giants, who are tied for second with Baltimore at 14.3. The Bills are sixth at 15.8.

Those three are also in the top 10 in sacks, with the Titans tied for second with the Steelers at 15, the Giants have 13 in three games to tie for fourth with the Jets and the Bills have 10 to tie for 10th with three other teams.

Getting after the quarterback is a must in this NFL. The three top teams in our rankings show just how important.

Poll Which unbeaten team has the best defense?   15%  Bills     27%  Giants     58%  Titans     Total Votes: 48576

The Cowboys fell from the top spot to No. 5 by losing to the Washington Redskins. Washington, which has won three consecutive games, is a big mover in these rankings, jumping from 12th to fourth.

They're not like the top three teams. They are 15th in scoring defense and have just six sacks to rank tied for 23rd with three other teams.

The Redskins are making their move behind young quarterback Jason Campbell. He has developed into a capable passing threat that gives them a chance every week.

I love watching the Cowboys' offense, but even I know a 20th-ranked defense isn't good enough. If that defense doesn't improve, their perch in the top five won't last long.

The Power Rankings though Week 4:

Power Rankings
Current		Team	Previous
	1	Colts · Trends	1
	Do they rest or play on? That is the question. If they're smart, they'll rest. The games don't mean anything. Health does.
	2	Saints · Trends	2
	The magic number is two to clinch home-field in the NFC playoffs. The defense hasn't played well without its starting corners.
	3	Vikings · Trends	3
	They bounced back in nice fashion from that disaster in Arizona and can clinch the division this week with a victory. They need help to catch the Saints.
	4	Chargers · Trends	5
	In usual Norv Turner fashion, the Chargers have turned it on after a slow start. They've won eight consecutive games. If they beat the Bengals this week, they will be getting the second seed.
	5	Eagles · Trends	6
	This is a team that can really score now. What will they be like when they have all the weapons on offense? Watch out for them come playoff time.
	6	Bengals · Trends	4
	I just don't think that passing game is close to being right. They have to get it going before the playoffs.
	7	Packers · Trends	10
	They have a playoff look about them now. That defense could help propel them to a run come playoff time.
	8	Cardinals · Trends	8
	Inconsistency showed up again Monday night in their loss to the 49ers. Why does that always happen with this team?
	9	Cowboys · Trends	7
	They head to New Orleans, trying to snap a two-game skid. Good luck against that team in that building.
	10	Broncos · Trends	9
	They get a big boost by a somewhat soft schedule down the stretch. Based on their final three games, they should be a playoff team.
	11	Patriots · Trends	11
	They just seem off, even when they win. And now they're in a race for the division title with Miami and the Jets. They can't afford a stumble.
	12	Ravens · Trends	16
	The schedule is favorable down the stretch, but there is no room for error. The key game will come in two weeks at Pittsburgh.
	13	Dolphins · Trends	17
	Is there any doubt that this is Chad Henne's team now? He will decide whether they are a playoff team or not.
	14	Giants · Trends	12
	It's the defense. They can't overcome their struggles on that side of the ball. Is a new coordinator coming?
	15	Jaguars · Trends	13
	Their playoff chances pretty much come down to beating Indianapolis on Thursday. We know that won't be easy.
	16	Jets · Trends	18
	They have a tough closing schedule, but helping might be the Colts clinching the No. 1 seed and the Bengals maybe playing for nothing in the final week.
	17	Steelers · Trends	14
	They're not officially out, but they might want to start vacation planning a little earlier than normal. Mike Tomlin has not done a good job with this team.
	18	Titans · Trends	19
	They play a playoff game this week against Miami. Winner stays alive. Loser is in big trouble.
	19	Falcons · Trends	15
	They've just had way too many injuries, but they played a heck of a game against the Saints. They'll fight this week against the Jets.
	20	Texans · Trends	20
	The playoffs are not done yet. What they did against the Seahawks is what we've come to expect from this team.
	21	Seahawks · Trends	21
	Their trip to Houston this past Sunday was disgusting. The defense can't stop anybody.
	22	49ers · Trends	22
	They still have playoff hope -- slim as it may be -- but the good thing is they are starting to find out about Alex Smith. He might be a keeper.
	23	Bills · Trends	23
	They looked like a playoff team against the Chiefs. Of course, it was against the Chiefs.
	24	Panthers · Trends	24
	It looks like the next three games will be the last for John Fox in Carolina. Who's next as coach?
	25	Bears · Trends	25
	They're officially eliminated from playoff contention, which will bring even more scrutiny on Jay Cutler. Is Lovie Smith safe?
	26	Raiders · Trends	26
	Are they really that different a team when Bruce Gradkowski isn't in the game? It sure looks like it.
	27	Redskins · Trends	27
	You have to like the way they're still fighting. Jason Campbell has made strides as a passer. They need to keep him.
	28	Chiefs · Trends	28
	Matt Cassel isn't playing well right now. And that's being kind. Do they make a change? They should.
	29	Lions · Trends	29
	They pulled a no-show in Baltimore last week, but that's what young teams can do late in the season when they are done. It'll be interesting to see if Jim Schwartz can get his team to respond.
	30	Rams · Trends	30
	They're down to their third quarterback. Has this been a trying season for first-year coach Steve Spagnuolo or what?
	31	Buccaneers · Trends	31
	It's getting worse by the week. General manager Mark Dominik has a lot of work to do this offseason.
	32	Browns · Trends	32
	Beating the Steelers might be what keeps Eric Mangini in his job. Can they win two in a row?