NFL power rankings, Week 8: Broncos, Cowboys still on top

Week 7 is in the books. The biggest storyline from the action probably involves Peyton Manning's record-setting night against the Niners, with Manning's four touchdown passes propelling him into the No. 1 spot on the NFL's all-time career list. The 42-17 blowout also strengthened the Broncos' hold on the top spot in our power rankings this week, as Denver continues to prove that its defense is among the league's best.

Separating themselves from the pack

The 10 or so teams at the top of our NFL power rankings continue to separate themselves from the jumble of sometimes good, sometimes bad teams in the middle. The Cowboys won their sixth straight by sticking to their smashmouth equation. They represent the NFC's most impressive team to date. The offense is riding DeMarco Murray and the efficient play of Tony Romo, but the defense also has been surprisingly stout.

The Packers, likewise, won their fourth straight while dominating the Panthers. In Green Bay's last four games, Aaron Rodgers has passed for 8.96 yards per attempt while racking up 977 yards, 13 touchdowns and no picks. If Rodgers can continue his dominant level of play, the Pack will be setting themselves up nicely for a playoff run.

Meanwhile, the Cardinals, Ravens, Colts and Lions continue to impress. Arizona knocked off the Raiders at their place to improve to 5-1 and right now has a grapple hold on the tough NFC West, no small feat for a team that's missed or is still missing several of its most important players to injury or suspension. The Ravens, who blew out the Falcons, seem to have found a balance of efficiency in all three phases of the game: offense, defense and special teams.

The Colts, known more for Andrew Luck and their impressive offensive attack, made a statement this week by shutting out the Bengals at home. The Lions continue to ride their top-tier defense and a newly balanced offensive attack, and won their second straight in comeback fashion. Detroit again rises in the rankings. The Patriots rise as well after stealing a victory away from the Jets with a last-second blocked field goal.

The only team from the top 10 to lose this week was the Chargers, who dropped a tough one at home to the Chiefs. Philip Rivers came back down to earth after having the best start of any quarterback this season, throwing for 205 yards on 17-of-31 passing, two touchdowns and a pick. Even with that subpar performance, Rivers is throwing an incredible 67.4 percent on the season for 8.5 yards per attempt, 1,961 yards, with 17 touchdowns and only three picks. If Rivers can get back on track, the Chargers will be fine.

Sliding into mediocrity

Meanwhile, the Seahawks continue to struggle and lost a wild, trick-play-laden game to the Rams in St. Louis. The defending champs have now lost as many games this season as they did in all of 2013, and need to figure out a way to get their swagger back before it's too late. One positive for the Seahawks is that despite giving away Percy Harvin to the Jets this week, the offense showed signs of life. Russell Wilson had his best game this season, becoming the first NFL quarterback to throw for 300+ yards and rush for 100 or more in a game.

Their archrivals in San Francisco also lost in disconcertingly punchless fashion, and the severely injury-hobbled Niners have a gut check this week after falling to 4-3. After a bye they'll host the Rams, who are undoubtedly playing with some confidence, but the 49ers will have a good chance to get things going in the right direction with a win.

Also falling into a tailspin, the Bengals lost big on the road to Indy, seemingly sapped of their energy after their overtime tie with the Panthers last week. The Bengals, who started out 3-0, now sit at 3-2-1, and while there's certainly still a lot of talent and potential in Cincinnati, it's always pretty devastating to get shut out in this league.

The Browns went down to Jacksonville this week with positive vibes after their blowout of the Steelers at home last week, but fell hard to the previously winless Jags. The Panthers, Bears, Giants, Texans and Saints all lost too, taking some luster off recent successes.

As for the rest

The Chiefs continue their Jekyll and Hyde act, knocking off the high-flying Chargers on the road and propelling them back upwards and into the 13th spot. The Bills gutted out a win against the Vikings, the Dolphins went into Chicago and knocked off the Bears, and the Rams, as noted, used ballsy special teams play calls by Jeff Fisher to upset the Seahawks, moving themselves up and out of the cellar. Washington beat the Titans to move up a few spots as well.