When an NFL owner comes to town and spends five hours in an interview, as Jets owner Woody Johnson did with Ryan on Sunday, then it's pretty serious business, and now it becomes only a matter of time.
But Ryan's loss could have major ramifications for the Ravens. Throughout the franchise's time in Baltimore, there have been two constants. One has been general manager Ozzie Newsome, and the other has been an heir apparent on the staff to become the next defensive coordinator to run The System.
If Ryan leaves, who is next?
"I don't know the answer to that one," Ryan said.
In Baltimore, the system has become just as important as the coordinator. Former coordinator Marvin Lewis, now the head coach of the Cincinnati Bengals, instituted it in 1996 when the Ravens moved here from Cleveland.
Lewis brought the philosophy - built on agile linebackers and pressuring the quarterback - from Pittsburgh, where it's still in place.
When Lewis left after the 2001 season, the Ravens had Mike Nolan. When Nolan left in 2004 to become head coach of the San Francisco 49ers, Ryan took over. From Jack Del Rio to Donnie Henderson, there have always been good coordinator candidates.
But now, with Harbaugh in his first year, we don't know who is next in line. Under former coach Brian Billick, there was always speculation that Vic Fangio, special assistant to the head coach, would be Ryan's replacement.
Fangio is still with the Ravens, but the players think he is too stiff, too robotic. Outside linebackers coach Mike Pettine would be a candidate because he has been with the Ravens since 2002. But once Ryan leaves, Pettine will likely leave with him.
Logic would dictate the Ravens hire someone on staff who is familiar with the defense and also someone Harbaugh hired, not a leftover from the previous regime. The top two candidates would be linebackers coach Greg Mattison and secondary coach Chuck Pagano, both of whom Harbaugh hired.
They have at least a year in a system that has been extremely successful. Nolan operated a different system when he was with the Jets, New York Giants and Washington Redskins, but once he took over in Baltimore, he did it the Ravens' Way.
For a lot of Ravens, such as defensive tackle Haloti Ngata, linebackers Terrell Suggs, Bart Scott and Jarret Johnson, cornerback Chris McAlister and safety Ed Reed, this is the only system they've played during their NFL careers.
And then there is the Ray Lewis factor. This is a scheme built around Lewis; he can run untouched from sideline to sideline to make tackles. As Nolan would often say, "This is Ray's world."
Nolan would be an ideal replacement, but there are reports that he will become the Denver Broncos' defensive coordinator. Marvin Lewis would also be a great candidate, but he can't get Bengals owner Mike Brown to fire him.
To bring in just about any other outsider would be a tough sell, especially if he wanted to install his own system. With a defense that has been as dominating as this one the past nine years, you want someone who not only knows the system, but who also knows the strengths, weaknesses and souls of the players.
One of the keys to the Ravens' success in 2008 has been the smooth transition to Harbaugh. It's a luxury to retain a coach such as Ryan and several of the assistants from the former staff.
Instead of having to butt heads with the dominating personalities of Lewis, Reed, Suggs and Scott, Harbaugh had Ryan a buffer. Harbaugh could send Ryan to solve any problem first, and if that didn't work, then Harbaugh could step in.
But those days are close to being over. In Ryan's four seasons as defensive coordinator, the Ravens have not finished below No. 6 in the league in total defense. His players play hard for him because he has a stern, but not overwhelming, personality, and he likes to have as much fun as they did.
That's going to be tough to replace.
Who's next? We don't know.
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