Monte Kiffin won't return to the Dallas Cowboys coaching staff a year after he was demoted from defensive coordinator job.
A person with knowledge of the decision said Wednesday that Kiffin, the assistant head coach under Jason Garrett last season, wouldn't return. The person spoke on condition of anonymity because the team wasn't planning to announce Kiffin's departure.
Kiffin, who turns 75 later this month, wasn't under contract for next season. He came in as defensive coordinator in 2013 to implement a scheme change to a four-man front after Dallas spent nearly a decade with a three-man line and four linebackers.
Rod Marinelli joined the staff along with Kiffin and was promoted to defensive coordinator in 2014 after the Cowboys had one of the worst seasons statistically in NFL history. Marinelli recently signed a three-year contract after Dallas showed significant improvement on defense while reaching the playoffs.
Kiffin just completed his 49th season as a coach, most of those in the NFL. He was the architect of a Super Bowl-winning defense in Tampa Bay, where he spent 13 years.
The first 17 years of Kiffin's career were in the college ranks, starting with 11 seasons at Nebraska, his alma mater. He also spent four seasons on the staffs of his son, Lane Kiffin, at Tennessee (2009) and Southern California (2010-12).
Kiffin's other NFL stops have included Green Bay, Buffalo, Minnesota in two stints, the New York Jets and New Orleans.