"We didn't win many games, but we sure fought as hard as we could," O'Brien said of his tenure at Duke.
Roof, who was at Central Florida for 33 days, spent three seasons as the defensive coordinator at Auburn. Roof essentially was pushed out the door at Auburn amid heavy criticism, leading to his hiring at Central Florida. Of course, Auburn did win the BCS national championship the season before.
Roof is noted for the ability to shut down the pass, but his defenses have struggled against the run, including being ranked 80th in the NCAA this season.
Roof also has coached at Louisville and Minnesota.
Penn State also reportedly has hired Ball State offensive line coach John Strollo, who is expected to coach tight ends.
Strollo just finished his first season at Ball State, but has been a college coach for 31 years. He was the offensive line coach at Duke from 2005 to '07, where he worked with O'Brien and Roof.
The news was first reported by Indiana television station WIOU. A Ball State spokesman said the school was not confirming the report and that an announcement would have to come from Penn State. Strollo did not return a message left at his office at Ball State.
His resume also includes stops at Springfield College, Northeastern, Washburn, Massachusetts, Lafayette, Cornell, Maine and Elon.
At this point, six coaches on O'Brien's staff have been identified - returning defensive line coach Larry Johnson and linebackers coach Ron Vanderlinden, and newcomers Roof, Strollo, running backs coach James London and wide receivers coach Stan Hixon. London was an offensive quality control coach with the Tennessee Titans. Hixon was the wide receivers coach with the Buffalo Bills.
O'Brien told ESPN on Sunday that he will have seven full-time coaches working in State College by tomorrow.
Not returning to Penn State is safeties coach Kermit Buggs, who tweeted his departure yesterday morning.
