Jerod Mayo retired as a player in 2016 after the AFC Championship loss to Denver. He went on to do TV locally with NBC Sports Boston, and he was good. But there is something about an NFL player that they can see things that the average person doesn't. Mayo was always a smart football player, meaning his football intelligence just made him better at reading plays as or before they developed.
I love it. I love that Mayo is like a player coach, just like Reg Dunlop for the Charlestown Chiefs. Makes sense though, you retire, do TV, realize that fire is still in you and you get back on the field any way you can. If Bill Belichick trusted Mayo as the defensive captain as a player, you know he's going to as the defensive play caller, even if he's listed as linebackers coach, you know he's the DC. Pepper Johnson and Brian Flores , the defensive coordinators before him were also linebackers as players. Smart football guys, trusted by Belichick, recipe for success.