Why they make sense: The Boston Bruins have a history of having legendary defensemen. Zdeno Chara. Bobby Orr. Brad Park. Ray Bourque. Paul Coffey. Why not add Karlsson to that lengthy who’s who of great defensemen? Especially with Chara at some point retiring? Karlsson could be the leader of a new blue line, the same way Zdeno has been.
A feasible trade: If the Senators are smart, they demand Charlie McAvoy. He’s an immediate replacement for Karlsson in Ottawa. But Boston isn’t trading him anytime soon. So the conversation starts with Torey Krug or Brandon Carlo.
Boston has already given up their 2018 first-rounder for Rick Nash, so that’s out of the question. But their 2019 first-round pick is still in play. Ottawa might actually value that a little bit more than a 2018 pick considering they might have to give up their 2019 pick in the Matt Duchene trade.
The final piece? Top forward prospect Jakob Forsbacka Karlsson. You’re not getting Erik Karlsson without giving up a top prospect. So the trade is Carlo, the Bruins 2019 first-round pick, Forsbacka Karlsson, and a mid-level prospect.
Why it won’t happen: Would the Senators give up a franchise legend to the Bruins? Nope, they prefer to let free agency do that for them. Also, Ottawa probably isn’t trading within the division. But if they do, Boston has enough prospects and picks to create a serious offer.