Quick look at new O-line coach Bill Callahan

The addition of Bill Callahan to the Cowboys’ coaching staff will provides Jason Garrett an offensive assistant with valuable experience as a head coach and play-caller.

Callahan, who ESPN’s Chris Mortensen reports will replace the retiring Hudson Houck as offensive coordinator, was the Oakland Raiders’ head coach from 2000-02 and also spent four seasons as the University of Nebraska’s head coach. He was 15-17 with the Raiders, who Callahan led to the Super Bowl in his first season as head coach, and 27-22 at Nebraska.

Callahan has been the Jets’ assistant head coach/offensive line coach since his stint at Nebraska. The Jets had an elite rushing attack in Callahan’s first three seasons, leading the NFL in rushing offense in 2009, but regressed badly this season, ranking 22nd in that category.

Callahan, who was the Raiders’ offensive coordinator before replacing Jon Gruden as the head coach, had offenses in Oakland that led the NFL in rushing (2000) and passing (2002).