The Connor Murphy that we saw with the Arizona Coyotes over the past three-plus years is not good enough to replace Niklas Hjalmarsson. That much I feel confident saying right off the bat after Hjalmarsson established himself as one of the few impact defensive defensemen in the NHL.
The Blackhawks used Hjalmarsson for their toughest assignments, and he often posted some of the lowest CA/60 (shot attempts allowed per 60 minutes) numbers of anyone on the team. Hjalmarsson was reliable defensively in a way that very few NHL defensemen can claim.