That trade involved P.K. Subban and Shea Weber, who each finished in the top 15 among defensemen in Yahoo's performance-based rankings last season. Subban will joins the Nashville Predators this season and could form the best pairing in the NHL with Roman Josi. Each has a realistic shot at 60 points; the last time two defensemen on the same team did that was Bryan McCabe (68) and Tomas Kaberle (67) for the Toronto Maple Leafs in 2005-06.

This offseason hasn't brought a lot of player movement along the blue line, but the outlook for fantasy defensemen heading into this NHL season did have a major change. Prior to the start of free agency, two big-name defensemen switched teams in a one-for-one trade, sparking plenty of debate in fantasy circles.

Weber will start anew with the Montreal Canadiens during a period of flux on their blue line. He will certainly miss Josi but should take over for Subban as quarterback of the Canadiens power play. Subban and Weber are elite fantasy producers at their position and switching teams shouldn't have a major impact on their ranking.

Video: MTL@LAK: Subban puts Canadiens on the board with goal

If there's any change that will have a significant impact on a defenseman's value and his team, it's Keith Yandle joining the Florida Panthers. Yandle figures to boost the Panthers' 23rd-ranked power play and should see plenty of ice time at even strength now that defensemen Brian Campbell, Dmitry Kulikov and Erik Gudbranson are no longer with Florida. Yandle ranks second among NHL defensemen in power-play points (92) over the past four seasons, two behind Subban. Durability and consistency are some of Yandle's traits; he has 47 or more points in three straight seasons and hasn't missed a regular-season game since 2008-09.

Campbell returned to the Chicago Blackhawks, where he had 19 goals, 117 points and a plus-51 rating in 215 games over three seasons from 2008-11. Campbell figures to be on the second pair with Niklas Hjarlmarsson and could see time on the second power-play unit. He won't score many goals or take a lot of shots, but Campbell will provide plenty of assists with a strong plus/minus despite his age (37).

A few additions to the top 50 include two Edmonton Oilers: Andrej Sekera and newly acquired Adam Larsson. Sekera is two seasons removed from scoring 44 points (11 goals, 33 assists) with the Carolina Hurricanes. Larsson comes from the New Jersey Devils, where he finished 63rd among defensemen in Yahoo's rankings last season. If the Oilers take the next step as a team, Sekera and Larsson could form a top defense pair to anchor a young, explosive offense.

Video: EDM@OTT: Sekera scores Oilers' second power-play goal

Here's a look at the updated fantasy defenseman rankings for standard Yahoo leagues (goals, assists, plus/minus, penalty minutes, power-play points, shots on goal), along with 10 players who just missed the cut. This list will continue to be updated leading up to training camp.

1. Erik Karlsson, OTT

2. Brent Burns, D/RW, SJS

3. Kris Letang, PIT

4. P.K. Subban, NSH

5. Dustin Byfuglien, D/RW, WPG

6. Shayne Gostisbehere, PHI

7. Roman Josi, NSH

8. Oliver Ekman-Larsson, ARI

9. John Carlson, WSH

10. Mark Giordano, CGY

11. Drew Doughty, LAK

12. Keith Yandle, FLA

13. John Klingberg, DAL

14. Shea Weber, MTL

15. Victor Hedman, TBL

16. Torey Krug, BOS

17. Duncan Keith, CHI

18. Rasmus Ristolainen, BUF

19. Aaron Ekblad, FLA

20. Tyson Barrie, COL

21. Brent Seabrook, CHI

22. Kevin Shattenkirk, STL

23. Justin Faulk, CAR

24. Dougie Hamilton, CGY

25. Ryan Suter, MIN

26. Jake Muzzin, LAK

27. Alex Pietrangelo, STL

28. Marc-Edouard Vlasic, SJS

29. Sami Vatanen, ANA

30. Seth Jones, CBJ

31. Colton Parayko, STL

32. Hampus Lindholm, ANA

33. Anton Stralman, TBL

34. TJ Brodie, CGY

35. Trevor Daley, PIT

36. Morgan Rielly, TOR

37. Michael Stone, ARI

38. Zdeno Chara, BOS

39. Ryan McDonagh, NYR

40. Alec Martinez, LAK

41. Mike Green, DET

42. Nick Leddy, NYI

43. Mattias Ekholm, NSH

44. Brian Campbell, CHI

45. Matt Niskanen, WSH

46. Ryan Ellis, NSH

47. Andrej Sekera, EDM

48. Jacob Trouba, WPG

49. Matt Dumba, MIN

50. Adam Larsson, EDM

Just missed: Andrei Markov (MTL), Dion Phaneuf (OTT), Johnny Boychuk (NYI), Cam Fowler (ANA), Alex Goligoski (ARI), Tyler Myers (WPG), Jared Spurgeon (MIN), Jason Demers (FLA), Jake Gardiner (TOR), Cody Ceci (OTT)