NFL Power Rankings: Which Teams Still Haven't Sold Themselves as Contenders?

Through three weeks of the NFL season we're still learning a lot about every team in the league.

All we really know at this point is that the Green Bay Packers look as good as they did last season, the Detroit Lions are better than anyone expected and the Indianapolis Colts and Kansas City Chiefs are in for long seasons.

We also know that the San Diego Chargers and Pittsburgh Steelers have not proven themselves to be contenders despite both squads having 2-1 records.

Under head coach Norv Turner, the Chargers have been notoriously slow starters. This year has been no exception, as San Diego owns lackluster wins over two 0-3 teams. The Bolts barely slipped by the Minnesota Vikings 24-17 in Week 1, were spanked by the New England Patriots 35-21 in Week 2 and eked out a win over the Chiefs 20-17 in Week 3.

Philip Rivers is the engine that propels the Chargers' offense and he has struggled more in the first three weeks than we have seen over the past few seasons. Rivers has completed 86-of-126 passes (68.3 percent) for 979 yards, but he has just four touchdowns and six interceptions. His quarterback rating of 82.1 is much lower than we've come to expect from the North Carolina State product.

If Antonio Gates can't return to full speed from a foot injury any time soon, it will be much harder for Rivers to get himself going.

San Diego's defense has been decent, aside from getting absolutely torched in Week 2 against the Patriots. The key to the season will be Rivers protecting the ball better than he has to this point. If the offense can get on track and look like everyone expects it to, the Chargers will elevate themselves to contender status.

The Pittsburgh Steelers were embarrassed in a 35-7 loss to the Baltimore Ravens in Week 1. Since then they have won two straight games, but those wins have come against lackluster competition.

Pittsburgh smoked an awful Seattle Seahawks team 24-0 in Week 2 and barely snuck by a horrendous Indianapolis Colts team 23-20 on Sunday night.

The defending AFC champs have had major problems protecting quarterback Ben Roethlisberger. Through the first three weeks, Big Ben has been sacked nine times and taken 13 additional hits.

The Steelers have also failed to get a running game going, as they are averaging just 85.7 yards per game on the ground (23rd in the NFL). Unless the offensive line can open some holes in the running game and protect Roethlisberger, there is no way Pittsburgh can be considered a serious contender.

This Sunday's matchup against the Houston Texans will tell us a lot about how good the Steelers really are.

NFL Power Rankings Week 4

1. Green Bay Packers (3-0)
2. New Orleans Saints (2-1)
3. Baltimore Ravens (2-1)
4. New England Patriots (2-1)
5. Detroit Lions (3-0)
6. Buffalo Bills (3-0)
7. New York Jets (2-1)
8. Pittsburgh Steelers (2-1)
9. San Diego Chargers (2-1)
10. Houston Texans (2-1)
11. Dallas Cowboys (2-1)
12. Philadelphia Eagles (1-2)
13. Tampa Bay Buccaneers (2-1)
14. New York Giants (2-1)
15. Washington Redskins (2-1)
16. Oakland Raiders (2-1)
17. Tennessee Titans (2-1)
18. Atlanta Falcons (1-2)
19. San Francisco 49ers (2-1)
20. Cleveland Browns (2-1)
21. Chicago Bears (1-2)
22. Carolina Panthers (1-2)
23. Miami Dolphins (0-3)
24. St. Louis Rams (0-3)
25. Cincinnati Bengals (1-2)
26. Minnesota Vikings (0-3)
27. Arizona Cardinals (1-2)
28. Denver Broncos (1-2)
29. Jacksonville Jaguars (1-2)
30. Seattle Seahawks (1-2)
31. Kansas City Chiefs (0-3)
32. Indianapolis Colts (0-3)