LOUISVILLE, Ky. (AP) -Former Duke coach Ted Roof was hired as a Louisville football assistant Thursday, more than five weeks after he was fired by the Blue Devils.

Roof replaces Reggie Johnson and will work with linebackers under Cardinals coach Steve Kragthorpe, who is shaking up his staff after a 6-6 season.

Roof went 6-45 in four-plus seasons at Duke. Before joining the Blue Devils, he spent four years at Georgia Tech, including three seasons as defensive coordinator.

Louisville also announced the hiring of former Michigan defensive coordinator Ron English. English said he had accepted the same position with the Cardinals on Monday, when the Wolverines beat Florida 41-35 in the Capital One Bowl. He was not retained by new Michigan coach Rich Rodriguez.

``Ron brings an intense passion for the game of football and his enthusiasm is contagious,'' Kragthorpe said.

Kragthorpe will serve as receivers coach next season. He fills the slot held by Charlie Stubbs, who was the receivers coach and offensive coordinator last year before stepping down.