Did I miss something? Which 'big-ticket' defensemen were on the market this summer?
There weren't any, and are a rarity to begin with. However, contrary to popular belief, trading Bobby for that package actually probably gained us ammo if such an opportunity arose, not the other way around. In the unlikely event a high end defenseman becomes available, it will almost certainly be from a rebuilding team, and a guy like Bobby Ryan probably doesn't entice them all that much. But, by adding two forwards with pretty good potential and a first round pick, that adds even more bullets for such a deal. You look at Ottawa, who had many bullets of their own, and were able to get a guy like Ryan. Now we're in the same position, and just have to play the waiting game.
As for who, biggest candidate on the horizon I can see is Brent Seabrook. Hawks obviously will want to keep him, but the salary cap might have a say in that. Toews and Kane are both due up at the end of 14/15, will surely demand deals similar, if not exceeding, to Perry and Getzlaf, and Crawford's extension kicks in for next year. That alone is probably upwards of $10 million. Even with some expirings and whatnot, it's feasible that they'll look to deal Seabrook, especially with all the rumors of such prior to the playoffs. Giordano's another one. Not right now, as Jay Feaster is a crazy person and considers him untouchable, but once the inevitable happens and Burke takes over, if he's willing to waive, then it's a definite possibility. It's certainly possible that he and Glencross refuse to waive, hence the untouchable talk, but I know his does expire before his contract does.
