Ted Roof resigned Wednesday after spending only one year as Penn State's defensive coordinator. He'll now take on the same position at his alma mater, Georgia Tech.
Secondary coach John Butler was promoted to defensive coordinator to replace Roof, getting the nod over longtime assistants Ron Vanderlinden and Larry Johnson.
"I've known Ted for a long time, and I'm excited that he has decided to come back to Georgia Tech," coach Paul Johnson said in a prepared statement. "He's one of the most respected football coaches in the nation."