This is the eighth in our series of position-by-position rankings. It is a little different this season because we’re ranking the players before free agency starts and before rosters are set. We will adjust accordingly as we go along. On to a stacked group of defensive backs:

1. Nnamdi Asomugha, Oakland: This may change. Many league observers expect Asomugha to leave the Raiders when free agency starts. That would be a major hit to this list.

2. Champ Bailey, Denver: Bailey is aging, but he is still an elite-level player.

3. Eric Berry, Kansas City: Berry could be atop this list next year. The second-year safety appears to be a special player.

4. Quentin Jammer, San Diego: The veteran cornerback is underrated. He is a stalwart.

5. Brandon Flowers, Kansas City: He is a favorite of NFL scouts. He is becoming one of the better young cornerbacks in the league.

6. Eric Weddle, San Diego: He is a top safety and a playmaker.

7. Stanford Routt, Oakland: This is a big year for Routt, who just signed a big contract with the Raiders. He’ll be challenged if Asomugha leaves.

8. Antoine Cason, San Diego: Cason is an up-and-coming player. He was very solid is his first season as a starter last year.

9. Brandon Carr, Kansas City: Carr is a strong right cornerback. He and Flowers make a nice tandem.

10. Bob Sanders, San Diego: The new Charger has to show he can stay healthy. If so, he’ll be a great pickup.

11. Tyvon Branch, Oakland: Branch is a good, strong player, but he still has to improve.

12. Michael Huff, Oakland: Huff is decent, not great. He could leave in free agency.

13. Andre Goodman, Denver: He is nearing the end of his career, but he’ll probably start in 2011.

14. Brian Dawkins, Denver: This could be his final season.

15. Steve Gregory, San Diego: He is a solid role player.

16. Kendrick Lewis, Kansas City: Lewis and Berry could be a pair for years.

17. Chris Johnson, Oakland: He could start if Asomugha leaves and the youngsters aren’t ready.

18. Javier Arenas, Kansas City: He could be a good nickel for the long term.

19. Mike Mitchell, Oakland: It’s time for this 2009 second-round pick to make a move.

20. Rahim Moore, Denver: I have a feeling this second-round pick will be ranked much higher next year.

21. Quinton Carter, Denver: The same may be said for Carter.

22. Marcus Gilchrist, San Diego: The second-round pick will get a chance to contribute early.

23. DeMarcus Van Dyke, Oakland: The third-round pick is a speedster.

24. Chimdi Chekwa, Oakland: The fourth-round pick got great experience at Ohio State.