This guy (Points upward)...
So Schwartz is out as an option at Defensive Coordinator. The next name on everyone's lips has been the in-house option in LB coach Mark Duffner. I'm not saying it won't happen (I would be delighted if it did), but I don't think this is the slam dunk option everyone thinks it is. Duffner and Coyle are SUPER close. They've worked together a very long time and it may not exactly be the easy sell to Duffner, "Hey, we are firing the guy who brought you in and is responsible for helping your career out a ton...take his job please?" Yes, that does happen in the NFL, but not every person is comfortable with that.
I want to pull another name out of the Dolphins coaching hat: Lou Anarumo, the team's current cornerbacks coach. He has a merchant marine background, which would gel nicely with Dan Campbell's "You're with me or take a long walk off a short plank" approach, and has certainly worked with successful defensive systems at various colleges. He is green, but the argument could be made that someone with a bit more openness to defensive scheme could suit our defensive personnel better. It's also not lost on me that there simply aren't many options if Duffner says no.
Unlike Lazor, whom I feel did not see eye to eye with Joe Philbin and could be happy to open up his offense more, I would NOT bring back Kevin Coyle. It destroys a lot of the good will fostered with the Dan Campbell signing. Plus, the guy already knows the team tried to replace him, and Tony Sparano-ing another coach is not something I can stomach.