Eberflus joins the 49ers after spending the previous season (2025) as the defensive coordinator for the Dallas Cowboys. He went to the Cowboys after a three-year stint (2022-24) as the head coach of the Chicago Bears.

Prior to his time with the Bears, Eberflus spent four seasons (2018-21) as the defensive coordinator for the Indianapolis Colts after seven seasons (2011-17) with the Cowboys, serving as the defensive passing game coordinator (2016-17) and linebackers coach (2011-15). Eberflus began his NFL coaching career with the Cleveland Browns, where he served as the team's linebackers coach for two seasons (2009-11).

Before entering the NFL, Eberflus spent 17 years (1992-2008) at the collegiate level. He served as the defensive coordinator for the University of Missouri for eight seasons (2001-08). He began his coaching career at his alma mater, the University of Toledo, where he served as defensive backs coach (1999-2000), outside linebackers coach (1994-98), a graduate assistant (1993) and a student assistant (1992).

Eberflus joins the 49ers after spending the previous season (2025) as the defensive coordinator for the Dallas Cowboys. He went to the Cowboys after a three-year stint (2022-24) as the head coach of the Chicago Bears.

Prior to his time with the Bears, Eberflus spent four seasons (2018-21) as the defensive coordinator for the Indianapolis Colts after seven seasons (2011-17) with the Cowboys, serving as the defensive passing game coordinator (2016-17) and linebackers coach (2011-15). Eberflus began his NFL coaching career with the Cleveland Browns, where he served as the team's linebackers coach for two seasons (2009-11).

Before entering the NFL, Eberflus spent 17 years (1992-2008) at the collegiate level. He served as the defensive coordinator for the University of Missouri for eight seasons (2001-08). He began his coaching career at his alma mater, the University of Toledo, where he served as defensive backs coach (1999-2000), outside linebackers coach (1994-98), a graduate assistant (1993) and a student assistant (1992). 

A native of Toledo, OH, Eberflus played linebacker at Toledo for four seasons (1990-93), earning First-Team All-MAC honors twice. He graduated from the school with a bachelor's degree in education.