Lets face it This is the main reason Scott was brought in. Who he fights is in question. Buffalo probably wants it to be Lucic . Boston wants it to be Thornton, as that is his job after all , enforce and stick up for teammates.
Personally, I think Thornton may have issues with Scott's size & reach and for that matter I don't think Lucic is a good match up either. He's very strong but isn't a real fast puncher. Factor in the 4 inches and 40 lbs it could be trouble. As for Thornton what a tough match up. Six inches and 50 lbs could give him a lot of trouble. I know he did well against boogey but I don't think boogey was at his best . Take nothing from Thornton he's a great tactical fighter and usually finds a way to hang in or upset big guys.
This leads to Chara who obviously matches up best size wise. Will Scott beat Thornton or Lucic and force a battle of the giants. It's kind of what I want to see and think may happen! Probably wishful thinking.