‘The Bills, under the first-year defensive coordinator Perry Fewell, have relied on frequent substitutions, creating opportunities for several players who may otherwise be buried on the depth chart. The defense has also relied on aggressive blitzing and stunts, playing to one of Denney’s strengths: speed. Linebacker Takeo Spikes said, “If you want this scheme to work, you need guys up front coming off the ball, being unselfish, and develop some depth,” so there is not a drop-off when a starter is out.”‘