PITTSBURGH -- Although Steelers coach Mike Tomlin vowed change following an early exit in the playoffs, at least one significant face on the coaching staff is staying the same.

Defensive coordinator Keith Butler is returning to his role with the Steelers for at least one more season, a source confirmed to ESPN. The news was first reported by the Pittsburgh Post-Gazette.

Butler, 64, has been with the organization since 2003 and in his role as defensive coordinator since 2015. Butler's previous contract expired at the end of the 2020 season.

The Steelers' defense finished as a top-five unit, finishing first in a handful of defensive categories, such as opponent total QBR (55.9) and sacks (56).

The unit, though, declined in the final month of the season. Once the league's best run defense, the Steelers finished allowing 111.4 rushing yards per game and 4.31 yards per carry, good for 11th and 13th, respectively, in the league. The passing defense was stronger, holding opponents to 194.4 passing yards per game and 5.91 yards per attempt, both ranking third in the NFL.

The Steelers previously parted ways with a handful of coaches, including offensive coordinator Randy Fichtner, offensive line coach Shaun Sarrett and defensive backs coach Tom Bradley. Other coaches on staff also have expiring contracts and their futures haven't been determined.

The Steelers also are expected to elevate quarterbacks coach Matt Canada to offensive coordinator, a source told ESPN last week, but the deal hasn't been finalized.