Could Leafs Trade Marner To Dallas For Stud Defenseman?

"The Toronto Maple Leafs are one of many teams that won't be done any favours by a flat cap in 2020-21. Maple Leafs' general manager Kyle Dubas will have to find creative ways to strengthen his defensive group with a tight cap. Luckily for the Leafs they do have one wild card up their sleeve, aside from John Tavares all their young forwards don't have any sort of trade protection. So if need be, the Leafs can always trade one of Auston Matthews, Mitch Marner or William Nylander for an elite defenseman with an equal or lesser cap hit. Could the Leafs trade Marner to Dallas for young stud defenseman Miro Heiskanen? That's exactly what Luke Fox of Sportsnet was asked in his latest mailbag and here's his response:"While I doubt either Jim Nill or Dubas is contemplating anything of the sort, it seems we've already rocketed to Planet Make-Believe, so why not play pretend?
The Toronto perspective (via me): Absolutely. Miro Heiskanen is a stud No. 1 defenceman at age 20, a young star with years of team control salary-wise. And while Mitchell Marner's deal was negotiated on the (fair) assumption the salary cap would only go up, Heiskanen has another year on his entry-level deal and two more after that before he even gets arbitration rights. «They don't come around very often like the way he is,» Jason Spezza marvels.
The Dallas perspective (via excellent Stars beat reporter Sean Shapiro): «Dallas would not do this trade. The more intriguing one to me is [John] Klingberg for anyone. Heiskanen untouchable.»"Would you make this trade if you could break Dallas into doing it?"