Despite not coaching in the NFL since 2016, Rex Ryan is reportedly emerging as the Broncos’ top candidate to serve as Sean Payton‘s first defensive coordinator in Denver, according to Ian Rapoport of NFL Network. The former NFL defensive coordinator and head coach would be making his first appearance on an NFL sideline since being fired by the Bills two years into a five-year contract. 
Before leaving the NFL, Ryan had been coaching football since 1987, when he served as a graduate assistant at Eastern Kentucky. After two years in the position, Ryan earned his first defensive coordinator position (along with a title of assistant head coach) at New Mexico Highlands University. The next year, Ryan would coach for a more notable school, serving as defensive coordinator at Morehead State.
Ryan would continue his rapid ascent from there, earning his first NFL job, with a little help from his father (and head coach in Arizona) Buddy Ryan, after four years at Morehead State. He spent two years as the defensive line and linebackers coach for the Cardinals before returning to the college ranks as defensive coordinator at Cincinnati. After two years with the Bearcats, Ryan served as defensive coordinator for Oklahoma for a year before returning to the NFL.
This time, Ryan’s move to the NFL would be permanent. Ryan accepted the job of defensive line coach for the Ravens, the team that would employ Ryan for the longest tenure of his career. Ryan coached a defensive line that helped the Ravens boast the best defenses in Baltimore history and, arguably, some of the best defenses in NFL history. He was rewarded with the defensive coordinator position five years later in 2005.
After a 2007 season that saw the Ravens finish 5-11, head coach Brian Billick and the rest of the staff were laid off. Ryan, being the coordinator of a defense that still ranked sixth in yards allowed despite the abysmal record, was an obvious candidate to replace Billick, but the job would go to current Ravens head coach John Harbaugh, who wisely chose to retain Ryan as defensive coordinator and promoted him to assistant head coach, as well. In his final season with the Ravens, Ryan led the league’s second-best defense in terms of yardage allowed (third-best in points allowed), assisting Harbaugh and rookie quarterback Joe Flacco in becoming the first rookie head coach and quarterback combo to advance to the AFC Championship game. In his ten years with the Ravens, the team never…