Harrison, in particular, improved from an undrafted practice squad linebacker into the NFL Defensive Player of the Year under Butler's tutelage.
[1] During his twelve-year tenure as the Steelers' linebackers coach, Butler was considered the heir-apparent for the defensive coordinator position held by the respected Dick LeBeau.
The Steelers defense was vastly improved in Butler's first season, increasing their sack total from the prior season 33 to 48, increasing their turnovers from 21 to 30, decreasing their points allowed by 4 per game, and leading the NFL in red zone turnovers.
One of the significant accomplishments during his tenure as Defensive Coordinator was that the Steelers “lead, or tied for the lead, in overall sacks for the last five years under Butler, setting an NFL record in 2020 when they did it a league-high four years in a row.”[4] Butler announced his retirement from coaching on January 22, 2022.
[4] Butler married his wife Janet in 1980 and together they have three adult sons, Blake, Brandon, and Brett.