"I understand what I have to do. I don't think it's going to be an issue. Sometimes when people see my demeanor on the sideline they may misunderstand. I'm incredibly competitive. While it may appear that I might have lost my mind, I haven't."
Butler, 39, was promoted Wednesday by head coach Bill O'Brien after Ted Roof departed to become defensive coordinator at Georgia Tech.
O'Brien chose Butler over two more experienced members of his staff, defensive line coach Larry Johnson and linebackers coach Ron Vanderlinden, the only two holdovers from the Joe Paterno era.
Butler said that while he doesn't know what Johnson and Vanderlinden thought about the move, he is confident they will be "100 percent in."
"I think I have a good enough working relationship with both of those guys, but I can't look into a crystal ball," he said. "But I made it very clear to them I hope that they continue in their roles and be great leaders of our defensive players."
Butler said the defense won't change much from 2012. He wants an aggressive defense with multiple looks but simple enough for players to pick up and play at a high tempo.
Penn State's defense lost a number of seniors who were major contributors to the team's 8-4 record - linebackers Michael Mauti and Gerald Hodges, ends Pete Massaro and Sean Stanley, tackle Jordan Hill, and cornerback Stephon Morris. Butler said that quality players would return, including defensive end and Northeast High graduate Deion Barnes, but that the team would be different.
"Every team takes on a new identity," he said. "We're trying to cultivate and develop leaders for this 2013 football team. That will take a life of its own. But I think we have a talented enough group as long as we stay healthy and move this thing forward."
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