Jim Leonhard bringing aggressive approach in transforming the Buffalo Bills defense

ORCHARD PARK, N.Y. (AP) — First-year Buffalo Bills defensive coordinator Jim Leonhard isn’t so much of an introvert, but rather someone who prefers sitting in the background and assessing a situation before offering his two cents.

It’s a tactical approach that helped the former undrafted free agent safety learn and adapt to the various defensive systems he encountered over a 10-year NFL career split over five teams, including two separate stops in Buffalo.

And it’s a quietly intense demeanor that’s led to Bills defenders calling Leonhard “the silent assassin.”

“He’s not going to say much to you, but what’s expected of you,” edge rusher Bradley Chubb said. “And I like it because at the end of the day you want stealth, that guy who’s not trying to be in the media and trying to do all this. He’s just about business.”

Leonhard laughed at the assessment, because it wasn't entirely wrong.

And yet, he also didn't want to be confused for being brooding or aloof because Leonhard, after all, is in a profession where player buy-in and comprehension are imperative — especially when starting from scratch as is the case in Buffalo.

“My job is to try to make that break-in period as short as possible,” Leonhard said.

“Over communicating is probably the No. 1 thing I can do to try to let them get in my brain, like, 'What am I thinking? How do I see this playing out?'” he added. “It’s being very open, which sometimes I don’t want to be. But that’s the fastest way.”

Time is of the essence after Buffalo's defense underwent a major overhaul this offseason in the wake of Sean McDermott’s firing in January.

As head coach, McDermott was also responsible for overseeing the defense during his nine seasons. Though his defensive bend-but-don’t-break philosophy was good enough for Buffalo to enjoy a seven-year run of double digit-win seasons, the unit too often underperformed in the playoffs.

Enter Leonhard, who at age 43 brings an attacking style approach he spent the past decade developing first in the college ranks as coordinator at Wisconsin, his alma mater. He then spent the previous two years working under coordinator Vance Joseph in Denver, a span during which the Broncos combined for an NFL-leading 131 sacks and ranked in the top 10 in various other categories.

Bills new head coach Joe Brady’s vision in hiring Leonhard was having the defense mirror the aggressive identity of his Josh Allen-led offense.

Buffalo is making the switch to a three linemen/four linebacker system, and will feature as many as five new starters. The many changing parts led to Leonhard fully anticipating the unit going through an early season adjustment period .

“There’s going to be mistakes. There’s going to be calls I want back,” he said on Thursday. “But if guys are playing fast, if they’re playing confident, if we’re able to communicate pre-snap with the calls, we’re going to give ourselves a really good chance to have success.”

Leonhard's vision of being aggressive is more nuanced than simply attacking on every play.

“That just means you're not going to let the offense dictate the game. We have to throw our punches too,” he said. “It's strategic. You're doing it on purpose. I don't like to be reckless as far as how I call a game. But I'm not just going to sit back and say, 'We're going to out-execute you week in and week out.'"

Leonhard was coy when asked how much of the defensive playbook he held back during open practices and three preseason games this summer.

“What do we benefit from me telling you how much you saw?” Leonhard said, with a chuckle as Buffalo prepares to open its season at Houston on Sunday. “I mean, there’s core elements to what we do that were obviously out there in the preseason. But at the same time, there is a lot more there.”

In typical Leonhard fashion, he is going to keep everyone guessing.

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