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A defensive mind | How Bills DC Leslie Frazier crafted a modern NFL defense while staying true to his roots


The Buffalo Bills are off to another hot start. They're 4-1 for the fourth season in a row. There are several among the organization that deserve recognition for flipping the franchise into a perennial playoff contender. One person that has to be at the top of that list is defensive coordinator/assistant head coach Leslie Frazier. 

Since Frazier came to Buffalo in 2017, the Bills have had one of the best defenses in the NFL. Since 2017, they've forced 140 takeaways (1st in the NFL), allowed just 89 passing touchdowns (1st, next best 113 – Vikings), allowed an average of a 78.0 passer rating to opposing quarterbacks (1st) and have given up an average of 20.16 points per game (3rd) and 310.2 total yards per game (1st).

Those numbers are jaw dropping, especially when the next best team has allowed 24 more passing touchdowns than the Bills. There's no challenge that's too big for Frazier, and the DC is not afraid to do something different in order to win. 

The Bills have a huge challenge this week against the team who leads the NFL in points per game (31.8) in the Kansas City Chiefs. Whatever magic Frazier mixes up to try to limit Chiefs QB Patrick Mahomes, his players will be right behind him ready to give it their all because of the trust and respect they have for him. 

This trust took time to build, but here's how Frazier has built one of the best defenses in the NFL over the last six years thanks to his experience and analytical mind.


Leslie Frazier played for the Chicago Bears from 1981 to 1985 and was a part of what many agree was the best defense in the NFL—the '85 Bears. After that season, Frazier got right into coaching and has been one ever since.

Having more than 25 years of experience in the NFL gives you a great handle on the people, the business and the qualities needed to be a successful coach.

"I think with Coach Frazier being a former player, he kind of understands the delivery," Bills linebacker Von Miller said. "He really knows how to label things, and he understands the perception that players have and that coaches have, and he's able to make this connection between the two."

Frazier played during the days where it was 'the coach's way or the highway'. Since then, the NFL and its players have changed quite a bit. So, Frazier got accustomed to switching it up in order to build a deeper bond with his players.

"When I came into the league, it was more when a coach says, 'This is how we do it,' this is how we do it," Frazier explained. "For today's player, it's not quite like that anymore. You have to give them an explanation sometimes because they're going to question you and ask why they have to do it that way. If you just say my way or the highway, you could be sitting in a room by yourself."

The veteran coach takes his time to lay out a scheme and gather input from his players while game planning for their opponents. Because of this philosophy, he has quickly gained trust and respect from his players.

"The guy is the true definition of integrity, just resilient," Bills linebacker Tremaine Edmunds shared. "I really respect him a lot, just as far as his approach to the game, his knowledge, his leadership skills. A lot of guys respect him. He's just been our leader."

Being a leader that has been in the NFL for many years as a player and a coach, Frazier thinks delivering a truthful message is important.

"I just try to be open with them and try to be honest," Frazier explained. "If there's a concern, I want them to know about it. When there's a chance to praise them, I want to praise them. But I want to be truthful to them. I think that's important."

"He's not afraid to, if he sees something, say it out loud," Edmunds said. "Guys respect that."

That respect is shown in the way players play for him, interact with him and talk about him. The group is willing to fight for Frazier because their relationship goes beyond the football field.


All coaches have a philosophy they base their defensive identity off of that aligns with a set of principles they preach. The way Frazier gets his players to believe in that message is with consistency.

"No matter how good a win is or how bad a loss is, he's always one to stay consistent throughout a game or an entire season," safety Jordan Poyer said of Frazier. "Things could be going terribly bad in the game. He's the one that you can look at as a coach and he's gonna calm everything down."

According to many players, you just know what you're going to get with the steady Frazier.  

At the start of every season, one of the first defensive meetings involves a message about the importance of a strong foundation. To display the need for one, Frazier will show a picture of a home being built.

Safety Micah Hyde missed out on the message this year, so Frazier called Hyde to catch the veteran up on what he had missed.

"Micah said, 'I know you showed the picture of that foundation,'" Frazier said laughing about Hyde's response. "But that's part of the consistency message that I think is so important for the players to hear."

This consistent messaging and the philosophy Frazier preaches was shaped by his former coaches. 

"I played for Buddy Ryan, he was my defensive coordinator and Mike Ditka was my head coach," Frazier said. "They had an aggressive mentality. But, in particular, being an attack-oriented defense. And I've kind of tried to carry that message over with our players."

For Buffalo, that message starts with stopping the run.

"We really emphasize stopping the run here on defense," Frazier said. "So we talk to them about that and how we do it here in Buffalo. And then we talk to them about affecting the quarterback because that's such a big part of winning games in our league. You got to be able to affect these really, really talented quarterbacks. We also talk about taking that ball away and trying to score on defense."

This season the Bills are affecting teams by stopping the run and putting the pressure on quarterbacks. They're allowing 77.8 rushing yards per game (2nd in the NFL), have forced 11 takeaways (tied for 1st) and have allowed just three passing touchdowns (tied for 2nd) so far this season.

While Buffalo has become known for the play of their star quarterback Josh Allen, plenty of national media members recognize Allen wouldn't be the same without a stout defense who gives him opportunity after opportunity to score.

"I'm no longer talking about the Bills without referencing Leslie Frazier," Marcus Spears said on NFL Live. "….You look at this defense and you look at how every single position complements the guy that they're next to. Edmunds (is) long ranging. Milano (can go) downhill, pull the pin, hit guys and is good in coverage. You look at how they've protected these young corners with their safety play and their linebackers getting a little more depth underneath to cover for those guys. 

"It's very impressive how he's able to accentuate what every guy's upper tier ability is in this defense. It's been marvelous."

Frazier knows the NFL loves its offense and points, and he understands that's not changing anytime soon. So, he's built his defense in a way that can limit athletic quarterbacks like Ravens QB Lamar Jackson and Chiefs QB Patrick Mahomes. The past few seasons, Frazier has played in nickel defense more than anyone else in the NFL. His roster makeup has allowed him to do that successfully thanks to an athletic, fundamentally sound defense that works as one.

"I think what Leslie Frazier does best and what stands out when you watch his team on film is the technique," explained Steven Ruiz, an NFL writer at the Ringer. "Anybody could call two high, just a random defensive coordinator could call it. But I think the way he coaches it and teaches it. I'm on the outside looking in so it's just based off film, but I feel like it's malleable, their zone defense and they can adapt to what the offense is running after the snap."


It's not easy to adapt, morph and shift to counter what an offense is doing, especially during a game. It's also not easy to change as the NFL changes when the league today looks way different than it did in 1981, but Leslie Frazier is willing to do whatever it takes to win.

In addition to the coaching and the personnel, one reason why the Bills have been so successful on defense is due to their trust in analytics.

"Technology has really revolutionized the game in so many ways," Frazier shared. "Analytics has become a big part of our game today. The person in charge of our analytics, Dennis Lock, is always providing me with information about a team's tendencies."

While preparing for every opponent, Frazier and his staff rely on analytics to reveal what they need to dig into when developing a game plan.

"All I have to do is say, 'Hey, Dennis, can you tell me when number 10 is in the game on 1st & 10, what are the tendencies? What do they like to do with number 10?,'" Frazier said. "Or, 'Hey Dennis, when number 25 is in the game can you put together a tape showing me all of his clips when he lines up on the left and on the right?' So, information like that makes my job a lot easier. But for me, I still go back to the tape."

Frazier describes his week as an ongoing conversation with the analytics department as he jumps from analytics to film to craft the most effective plan to stump his opponent. Analytics don't just help the DC, they also help his players better understand the why behind what they decide to do game to game.

"Sometimes you have coaches that say, 'Do it this way. This is how I want you to do it, and this is gonna work,'" linebacker Von Miller said. "Coach Frazier takes it a step further. He uses analytics, and he shows you why it works. He shows you why it matters, and I think that sticks a little bit more."

"We'll go into a meeting, and they'll say, 'If they come out in this, 92% of the time they're passing the ball,'" safety Jordan Poyer said. "So, after the play, I look to the sidelines. I see they're lined up in that and then I alert the pass. So, they do a great job with those type of analytics and it helps us anticipate."

That anticipation and the success of the Bills defense due to their use of analytics can be seen on film according to The Ringer's Steven Ruiz.

"The big thing in analytics over the last couple of years has been that the pass game is more important, more efficient than the run game," Ruiz explained. "And the way for defenses to counteract that is to play lighter run boxes and have two safeties deep. I don't think any team has exemplified that more than the Buffalo Bills over the last three years. That's the poster child for the analytical influence on defense in the NFL, you can see it."


Developing a strong trust with your players, sticking to your principles, knowing the league and welcoming anything that can help you win all leads to how you prepare your game plan every week in hopes of defeating your opponent. 

Frazier understands that all these things have to work in tandem together in order to have the best chance at winning. When it comes to Buffalo's plan to slow Chiefs quarterback Patrick Mahomes, the most vital part are his players. Frazier learned the value of personnel during his playing days with Chicago.

"When I came into the league, we were just okay on defense," Frazier said of his first few years with the Bears. "And all of a sudden, we start drafting people like Dave Duerson, Ron Rivera, Refrigerator Perry, Wilber Marshall. Those were great players in my era on the defense that I played on. And all of a sudden people were saying, 'What's this new defense that the Chicago Bears are running?' 

"I was like, it's same defense but the players have made the defense so popular and so much better. It's the same thing here. We have good players, and they make the scheme come alive. We are there to just guide them as coaches. We're fortunate in that way, you need good players to be sometimes a really, really good coach."

Von Miller, Tremaine Edmunds, Matt Milano, Ed Oliver, Jordan Poyer and more are the key players that make a scheme come to life for the Bills. The players have a big role, but it starts with a coach who has the mind to go outside of the box if needed and the trust in his players to do it. 

"There are times we look at ourselves and say, 'Okay, in order for us to win this game, we got to go against the grain. We got to do something that other people aren't doing,'" Frazier explained. "And then, you got to sell the players on that. You got to get them to believe that we can do it this way."

The perfect example of "going against the grain" was when the Bills decided to not blitz Mahomes once in Week 5, 2021 and beat the Chiefs 38-20. They did the same against Matthew Stafford and the Rams in Week 1 this season, which also ended in a resounding victory. After that game, there had only been three NFL games where a defense did not blitz in a game since 2016. The Bills owned all three, according to Next Gen Stats.

The Bills are more than willing to change their identity week to week because it's worked multiple times.

"One week we may not pressure very much, another week we may pressure more," Frazier said. "And the players got to buy into that and not feel like, 'Why are we changing?' Well, we're changing because this is what that team does, and this is what it will take for us to be successful against that team. You have to have trust in your players to do that."

"From week to week they're able to make little changes to better defend whatever offense is coming up," Ruiz shared. "I think their success against the Ravens over the past couple years is just proof of that because the Ravens are the most unique offense in the NFL because of what Lamar Jackson does, how they deploy personnel and how they run the ball."

Ruiz believes this play speaks to how good the underlying philosophy for the defense must be because in order to stop the run, you have to change part of your nickel defense's identify. 

Jordan Poyer has been a part of too many game plans to count under Frazier's watch. And it's the DC's ability to craft a plan, sell what they're doing and get the most out of his players that makes Poyer understand just how lucky he is to have Frazier as a coach.

"You don't just go out there and think, 'Why are we doing this right here?'" Poyer said. "You get the call and think, 'Okay, this is what we talked about in the meeting. This is why we're doing it.' He really teaches you the game of football. When you're in the game and you hear the call, it's like you've been there before."


The Bills coaching staff, scouting department and players know the team's overall success since 2017 goes hand in hand with the play of Buffalo's defense over the years. 

Leslie Frazier deserves a lot of credit for what he's done in Buffalo. It's not easy to adjust your coaching style over the course of 25 years in the NFL and it's not easy develop late-round draft picks into high-level players. Frazier is behind all of that.

While everyone in Buffalo would love to see him stay here for the long haul, they would love even more for him to get an opportunity at being a head coach again.

"My prayer is he can get that opportunity again some time," head coach Sean McDermott said. "I think he's earned it." 

"He could be a head coach for 31 other teams in this league right now," safety Jordan Poyer said. "That's saying a lot in itself right there. I think he's got the accolades. He's got the respect from everybody around the league."

The reason why he's respected by so many around the league is because he started by earning the respect of the teams he has played and coached for. If you ask the players here, they'll do just about anything for Frazier. 

Poyer, who is searching for an extension, wouldn't let that get in the way of an opportunity to play for Frazier for another year.

"I play this game, the way I play it for guys like Frazier, for my teammates," Poyer said. "So that opportunity is way bigger than anything."

A player who's willing to put something personal aside for a coach says a lot about that coach. That's Leslie Frazier. He's respected and loved by so many people across the NFL. And after you have the opportunity to be around someone like him, you know you're better off because of that time you spent with him.

"I think you should want a coach that is going to get the most out of his players, both physically and emotionally and that can also connect with his players both physically and emotionally," linebacker Von Miller said. "Coach Frazier does that. There is no magic card, there is no magic defensive scheme. The magic comes from the coach being able to get the most out of his players, getting everybody on that defense or on that team to be laser focused for 60 minutes on Sunday. That's Coach Frazier."

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