Wednesday, ESPN's Pierre LeBrun stated that he knows the Flyers have Predators' defenseman Ryan Suter at the top of their shopping list. Ryan Suter is very, very good. This often gets overlooked not only because he's in Nashville, but also because Shea Weber is even better than Suter and hitting free agency this summer as well.

With Chris Pronger done for the year, the Flyers are currently relying on some combination of three rookies (Marc-Andre Bourdon, Erik Gustafsson, and Kevin Marshall) and two not-so-good veterans (Andreas Lilja and Matt Walker) to fill their third pairing.

This would normally be cause for concern, but this group of shaky and/or unproven defensemen are just as good as the third pairing options the Flyers had last year, when nobody was worried about the need to acquire one of the best defensemen in the NHL.

Unfortunately (fortunately?) that doesn't stop the speculation about the Flyers acquiring Shea Weber, Ryan Suter, Cam Fowler, Luca Sbisa, Luke Schenn, or any other enticing defenseman. But what do defensemen cost on the trading market?

Here is a table of some of the best defensemen acquired in the last twelve months and what it cost to acquire them:

Table is sortable by column.

What Is the Cost?

Young defensemen don't often get traded. In the past calendar year, only one sub-25 defensemen was traded off an NHL roster.

Erik Johnson was taken first overall in 2006, but was traded along with a veteran defensive center and a first round pick in exchange for 22-year old, former first rounder Kevin Shattenkirk, 23-year old former first rounder Chris Stewart, and a second round pick.

Rundblad was traded along with a second round pick to acquire former number three overall pick Kyle Turris. This speaks more to the value of Turris than Rundblad, but as the centerpiece of that deal from Phoenix's perspective, he's worth including.

This is an admittedly small sample, but it's not a stretch to say the reason there are so few young defensemen traded is that these guys just aren't on the trading block. When they are, the cost of acquiring them is high.

Defensemen in their prime get traded more frequently, possibly due to them reaching unrestricted free agency sooner.

Burns was sent to San Jose along with a second round pick, but required a 24-year old three-time 20-goal scorer, San Jose's most recent first round pick, and their next first round pick.

Goligoski required a 23-year old, four-time 20-goal scorer AND a second round pick to get him to Dallas. (Yes, James Neal scored twenty goals in Dallas before being traded.)

Ballard cost a 23-year old former first round pick, a 25-year old three-time 15-goal scorer, and a first round pick.

Klesla cost a 27-year old three-time 14-goal scorer and a 26-year old former third round pick, both of whom had expiring contracts.

Campoli was essentially swapped for a second round pick, since the seventh-round pick was for an AHL center.

Wideman was acquired for a third round pick and an undrafted ECHL player, so he might have been the steal of the year. Especially when you consider that Dale Tallon had earlier that year acquired Wideman and a first round pick in exchange for Gregory Campbell and Nathan Horton. So Tallon turned Horton, Wideman, and Campbell into a 1st and a 3rd.

Older defensemen who still have the ability to play in the top four aren't traded too often, whether it be due to shorter contracts, signing with teams who are buyers at the deadline, having un-moveable cap hits, or something else entirely.

Kaberle - the first time he was traded in the last twelve months - was a deadline acquisition by the Bruins. Boston gave up a 21-year old former first round pick, their next first round pick, and a second round pick. The second time, he only cost a 37-year old Jaroslav Spacek.

Liles cost a second round pick.

Allen was acquired for Sergei Samsonov, a 32 year old who had scored 15 goals once in the last five years and may be out of hockey (his Wikipedia page says he's still an unrestricted free agent and hockeydb shows he hasn't played a game anywhere this year).

Summary

Young defensemen do not get traded often at all, but when they do, their price is high.

Prime-aged defensemen get traded fairly often, but they require top-6 forwards, second round picks, and/or Dale Tallon.

Older defensemen can cost very little, two first round picks and a second round pick, or anything in between.

Conclusion

What does this mean? Don't expect Luke Schenn to come any cheaper than multiple first round picks.

Ryan Suter and Shea Weber are 26 and 27 respectively, so they should cost something like a top-6 forward and a first round pick, if not more.

Meanwhile, Bryan Allen shouldn't cost much (maybe a third round pick or a Phantom with some potential) while still representing an upgrade over the Flyers current third-pairing options.

But where's the fun in Bryan Allen?