The Cowboys have hired former Oakland Raiders head coach Bill Callahan to replace the retiring Hudson Houck as offensive line coach, according to a source.
Callahan's hiring first was reported by ESPN's Chris Mortensen.
The Cowboys also requested permission to talk to Cleveland Browns defensive backs coach Jerome Henderson. They are expected to add the former NFL defensive back to their staff this week to replace Dave Campo.
Callahan, 55, spent the past four seasons as the assistant head coach and offensive line coach for the New York Jets. Three of his offensive linemen -- Alan Faneca, Nick Mangold and D'Brickashaw Ferguson -- combined for nine Pro Bowl appearances.
Callahan was 15-17 as head coach of the Raiders in 2000-02, including a Super Bowl appearance, and 27-22 from 2004-07 as head coach of the University of Nebraska.
He was the offensive coordinator of the Raiders from 1998-2001 before replacing Jon Gruden as head coach.
Houck, 69, also served as the running game coordinator. He was the league's highest-paid offensive line coach at $1 million per season.
Houck returned to the Cowboys in 2008. He first coached in Dallas from 1993-2001 before going to San Diego and then Miami. He spent 29 seasons coaching in the NFL.
The Cowboys have five other assistants with contracts set to expire. The Star-Telegram reported Monday that Campo will not return to the team.
Running backs coach Skip Peete, assistant offensive line coach Wes Phillips, secondary coach Brett Maxie and assistant receivers coach Keith O'Quinn also have expiring contracts.
The Titans have asked for permission to interview Maxie, whom the Cowboys would like to have back to pair with Henderson.
Henderson coached under Rob Ryan for two seasons in Cleveland. He was the Jets' defensive backs coach in 2008.
Staff writer Clarence E. Hill Jr. contributed to this report.