Butler, a La Salle High School graduate, is in his 19th season as a coach, but just his second with the Lions and first as the defensive coordinator. He was the secondary coach last year and got promoted when Ted Roof left for a job at Georgia Tech.
O'Brien said Butler is one of the best coaches he has ever been around, and though they have had only spring practice and a handful of days of training camp to face each other, it seems like they have a healthy dynamic.
"It is very competitive - in the office, out on the field - just mindwise. We're always busting each other's chops," Butler said at the team's Media Day last week. "He might say something, and I pick it up and bring it back to his attention. He's the head coach, I'm the defensive coordinator. I work for him, and I'm not going to cross the line, but I will push the envelope."
Butler is taking over a defense that gave up an average of 19.1 points (second in the Big Ten) and 356.3 yards per contest last season (fourth in the conference).
One aspect Butler has keyed on in his 7-month tenure is turnovers, which was evident last week at practice. During a goal-line drill, running back Akeel Lynch took a carry up the middle, and after the play was blown dead, a few Penn State players still took some swipes at the ball. Then, Butler jogged by Lynch, and he too made a pass at jarring the ball loose.
"Every day in the meetings, he's rewinding the tape and showing us different plays where we can attack the ball in a different way," senior safety Malcolm Willis said. "That's his motto, that's how a defense should be, we should be aggressive and always want to get the ball back to our offense."
Butler still will have more of an emphasis with the defensive backs, as he retains a role as cornerbacks coach. Anthony Midget was added to the Lions' staff in the offseason and is in charge of the safeties.
Penn State returns three starters to its secondary, but that does not mean the team is content. Willis noted that Butler and Midget always preach "satisfaction is for suckers."
The Lions also return some important players up front on defense, including linebackers Glenn Carson and Mike Hull, tackle DaQuan Jones and end Deion Barnes (Northeast High) - all of whom said the transition of having Butler in his new role has gone well.
And just as Butler will take pride in besting O'Brien, his players are working to beat their offensive counterparts at practice.
"It's exciting stepping on the field every day, because we're going up to the chalkboard and designing plays against what they're scheming, and doing stuff like that," Carson said. "It's almost like playing an opponent every day."
O'Brien said his offense - which does not yet have a starting quarterback - was a little behind Butler's defense at the beginning of training camp. While, the second-year head coach will work to change that, Butler will be right beside him attempting to keep it that way.
"It's a fun environment to work in, because you're always being motivated to win," Butler said. "And, heck, that's what this country is all about, man."
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