ORCHARD PARK, N.Y. (AP) - Rex Ryan reacts in mock surprise when reminded how young Preston Brown is, and the trust the Bills are placing in the second-year linebacker to command the huddle of their high-priced defense.
''Oh, gawd, I didn't realize he was 22. I'm a little nervous,'' the Bills new coach said. ''But no. He certainly has more of, I don't know if mature is the right word. But he's been around the game awhile.''
Since Brown was a toddler, to be specific.
The son of a Cincinnati-area high school coach, Brown recalls being five when his education in football began with an astute realization.
If he wanted to spend more quality time with his father, then it would have to be on his dad's turf: in the basement, where Mike Brown would spend hours poring over game film and devising plays at a big whiteboard.
''It was like watching TV with my dad,'' Brown recalled. ''I could watch film all day. That's just something that got real big for me.''
It was time well spent from both a personal and professional standpoint.
In establishing a close bond with his father, Brown also developed a high football IQ, which has allowed the 2014 third-round draft pick out of Louisville make a relatively seamless transition and render Kiko Alonso expendable in Buffalo.
As a rookie, Brown started 14 games and led the Bills with 108 tackles while playing in former defensive coordinator Jim Schwartz's 4-3 system. The defense finished fourth in the NFL in fewest yards allowed, had a league-leading 54 sacks and had three linemen earn Pro Bowl selections.
This year, Brown is already pegged to set the front-seven alignments in the huddle as the Bills make the switch to Rex Ryan and new coordinator Dennis Thurman.
''He's a smart guy, and you very seldom have to repeat things to him,'' Thurman said. ''Usually a coach's kid is going to have that mental aptitude because he's been around the game for a long time. He's taken to the call. He seems very comfortable in the huddle.''
The Bills placed so much stock in Brown's ability that it eased their decision to trade Alonso to Philadelphia and acquire running back LeSean McCoy. Alonso, an NFL rookie defensive player of the year candidate in 2013, was expected to regain his starting role after missing all of last season with a knee injury.
Valuable as Alonso was, he became the odd man out because of Brown and the presence of fourth-year linebacker Nigel Bradham, who is expected to fill the other starting spot in the middle.
The Bills are also moving forward without veteran run-stuffing linebacker Brandon Spikes, who was not re-signed. Brown acknowledged he learned plenty from Spikes.
''It's been a whirlwind really of emotions and what's going to happen next,'' Brown said. ''But it shows the confidence they have in us right now that they believe we can go out there and play at a high level.''
Listed at 6-foot-1 and 251 pounds, Brown has the range to move laterally, and the willingness to take on blockers - two things he'll have to adjust to in the new defensive scheme.
Having a command of the system and confidence to call plays shouldn't be a problem after being a three-year starter at college.
''It's fun. I'm a 22-year-old guy telling these old guys what to do,'' Brown said.
It goes back to the basement, and Brown learning the game from his father, who is now retired.
When he was being recruited to play college, Brown recalled how his dad would invite visiting coaches downstairs to draw up defensive plays on the whiteboard.
''It's not really hard to just pick up things,'' he said. ''He could teach me a play, and I'd go out there and do it.''
Brown would also draw up plays, which his father would critique.
''He still says my circles and squares are off,'' Brown said, with a laugh. ''But I'm trying to get better at it.''
One step at a time.