Air Force defensive coordinator Charlton Warren has been hired to coach Nebraska's secondary.
Coach Bo Pelini on Friday announced the hiring of the replacement for Terry Joseph, who left two weeks ago to become secondary coach at Texas A&M.
The 37-year-old Warren is the Cornhuskers' fourth secondary coach in five years. He was on Air Force's staff for nine years, the past two as associate head coach and defensive coordinator.
The Falcons ranked third nationally in average passing yards allowed and sixth in pass efficiency defense in 2011. Air Force started two sophomores, a junior and senior in the secondary in 2013 and ranked 78th in pass defense.
Warren played defensive back at Air Force, graduating in 1999. Nebraska did not release salary information.