B/R Debate: Who Is Buffalo Bills Key Defensive Player Not Named Mario Williams?

The Buffalo Bills have almost completely revamped their defense, and adding defensive end Mario Williams gave them a cornerstone around which to build the whole operation.

But as important as he'll be to the defense, he's not the only guy who has to make an impact.

So who is the second-most important defensive player to the Bills defense as they try to turn things around from 2011?

To debate the topic, we bring in Bleacher Report Bills featured columnist Chris Trapasso, who can also be found on Twitter.

Take it away, Chris.

Chris: It's easy to list Marcell Dareus and Kyle Williams, guys who'll affect Mario's impact on the team's pass rush in 2012, but I'm going with safety Jairus Byrd. He burst onto the scene in 2009 with nine interceptions as a rookie, but he wasn't much more than a center fielder who was the beneficiary of a few lucky bounces.

Last year was Byrd's best as a professional. He had 98 total tackles, one sack, three forced fumbles, three interceptions and was around the football much more.

Due to the improved pass rush, the fourth-year safety from Oregon is in a prime position to take that next step and become one of the league's better all-around safeties.

Although Buffalo's been atrocious against the run over the last three seasons, they weren't exactly stingy against the pass in 2011. Quarterbacks averaged a 90.4 QB rating and tossed 30 touchdowns when playing the Bills last season.

If Byrd can become an even bigger presence in the box against the run while capitalizing on hurried throws from opposing signal-callers, the Bills will be well on their way to having a strong and balanced defensive unit.

Erik: Byrd will be an important piece to the Bills' future in the secondary—and the present as well—but I'm going with linebacker Nick Barnett.

At 30 years old, Barnett's future may be shorter than his past, but a steady veteran presence is as important a cog in the defense as any young player—if not even more so—specifically in Barnett's role.

The Bills are installing a new defense, and with that, they need someone who has experience in the defense to make sure everyone's on the same page and everyone knows their responsibilities. As cliché as it may be, Barnett has been the quarterback for plenty of 4-3 defenses in the past. He was the leader of the pack for the Packers' 4-3 defense from '03-'10, leading the team in tackles four times in that span.

He was also a long-standing team captain for the Packers.

What's more, there have been improvements on the defensive line and in the secondary, but the Bills haven't made any significant adjustments or improvements at linebacker. A high-performing season from Barnett will be pertinent to the Bills' defensive advancements.

While Byrd will play a big role in helping the improvement in the secondary in 2012, Barnett's role as signal-caller of the defense will be important to the unit as a whole.

Chris: Barnett clearly plays a major role, but I'm not worried about him producing consistently. In terms of the linebacking corp, I'd say significant improvement from second-year pro Kelvin Sheppard will be more crucial to the Bills making a considerable stride on defense.

I picked Byrd because he can impact the game in a variety of ways, as was evident last season.

He sometimes lines up near the line of scrimmage and is depended upon to make plays against the run. Even when he's in more of a free safety role, his instincts and closing speed allow him to make tackles at the second level.

Along with that, he clearly is needed to be a force in the secondary by defending passes and intercepting the football.

A solid veteran linebacker is a renowned staple on all great defenses, but so is a reliable and heady safety. 

Erik: Not to compare Byrd to Ed Reed, but he could be that style of safety for the Bills as a talented ball-hawk with the sideline-to-sideline range to effectively take on Cover 1 responsibilities. He'll be even more effective in that role if the rest of the defense knows their calls and is in the right place to begin with, which will allow him to do more of that ball-hawking.

That's where Barnett comes into play. I'm looking at this more from a team-wide impact standpoint than an individual production standpoint. While there's plenty of benefit to a talented cover safety, Barnett projects as a leader for this defense on the field.

Yes, Byrd is a versatile safety and can play effectively against both the run and the pass. But whether Barnett is making the play or simply making the calls, his impact will be felt in both the passing and running game on every single down that he is on the field (in 2011, he lined up for 976 snaps—92.5 percent of the team total, per Pro Football Focus).

Barnett's veteran experience, guidance and leadership will all be key factors in the growth of the Bills defense as they look to move on from the woes of the 3-4 in 2011 and move forward to the new-look 4-3 front in 2012 and beyond.

And while Chris and I may not agree on which player is the most key defender besides Mario Williams, we can both agree that Byrd is more important to the long-term future of the defense, while Barnett is more important to the immediate transition from the 3-4 to the 4-3.

Thanks again for joining me, Chris, and we'll be sure to link up in the future for another Bills debate.

Readers can find a new debate on a wide range of Bills, Jets, Patriots and Dolphins topics every day at the AFC East blog.

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