The Las Vegas Raiders finally played solid defense last year after years of ineptitude. They finished the season ninth in EPA and fourth in weighted DVOA, putting the defense on the map.
Most of the credit will go to the emergence of the defensive line. According to PFF, Maxx Crosby and Malcolm Koonce became a dynamic tandem, finishing the season with 146 pressures between them. This dynamic displayed itself in the matchup vs. the Chiefs, where the two players had 16 pressures, and Koonce had three sacks on the day.
The safety group was an underrated position group that contributed to the rise of the defense.