For nearly a decade, the Buffalo Bills' defensive identity was as predictable as a lake-effect snowstorm in January. Under Sean McDermott, 'One Bills Drive' was the cathedral of the 4-3 base and the "big nickel" sub-package.
But on Thursday, new defensive coordinator Jim Leonhard didn't just open the doors to that cathedral; he began knocking down the walls.
In a candid, 30-minute introductory press conference, Leonhard laid out a vision for a defense that is "attacking, not reactive." For a fan base accustomed to a front four doing the heavy lifting while the back end played umbrella coverage, the shift is seismic.